Common Mistakes When Buying a Commercial Office Building

Most banks treat commercial property finance as a completely different product from residential lending.

The assessment process runs differently, the loan structures work differently, and the mistakes you make cost more. If you're planning to buy a commercial office building to house your business or as an investment, understanding how lenders approach commercial lending means you avoid delays, declined applications, and loan structures that lock you into inflexible terms.

Secured Business Loan vs Unsecured Business Finance

A secured business loan uses the commercial property as collateral, which gives lenders confidence to offer larger loan amounts and longer terms. When you purchase a commercial office building, the property itself secures the debt, and lenders will typically advance 60% to 70% of the property's value depending on location, tenant quality, and your business financial statements.

Unsecured business finance doesn't require property as collateral, but loan amounts rarely exceed $500,000 and terms are much shorter. You won't buy a commercial office building with unsecured finance unless the purchase price is unusually low or you're funding a small deposit top-up. The interest rate on unsecured lending also sits several percentage points higher than secured commercial loans, which compounds quickly over a 10 or 15-year term.

Consider a business owner looking to buy a small office building in an established commercial precinct. With a secured business loan, they can access 65% of the purchase price at a commercial rate, leaving them to fund 35% as deposit plus settlement costs. Attempting the same purchase with unsecured business finance would require funding almost the entire purchase price in cash, which defeats the purpose of leveraging debt to expand operations.

How Lenders Calculate Serviceability for Commercial Property Purchases

Lenders assess your ability to service a commercial loan using your business cashflow, not personal income. They review business financial statements, tax returns, and a cashflow forecast to determine whether your business generates enough profit to meet loan repayments, cover operating expenses, and maintain a buffer. The debt service coverage ratio is the metric most lenders use, and they typically want to see a ratio of at least 1.25 to 1.30, meaning your business generates $1.25 to $1.30 in cashflow for every dollar of debt repayment.

If the commercial office building you're buying will be leased to tenants, lenders also factor in rental income when calculating serviceability. A building with a strong tenant on a long lease improves your serviceability position significantly, while a vacant building or one with short-term tenants may require more equity or stronger business income to get the deal across the line.

In our experience, business owners underestimate how much weight lenders place on lease documentation. A signed lease with a creditworthy tenant for three years or more can be the difference between a 60% loan and a 70% loan, which on a $2 million purchase translates to an extra $200,000 in borrowing capacity.

Fixed Interest Rate or Variable Interest Rate for Commercial Loans

Commercial lenders offer both fixed interest rate and variable interest rate options, but the split isn't as common as it is in residential lending. Fixed rates on commercial loans typically lock in for one to five years, and break costs apply if you repay early or refinance before the fixed period ends. A fixed interest rate gives you repayment certainty, which helps with cashflow forecasting and budgeting for business expansion.

Variable interest rates on commercial loans come with more flexibility. You can usually make extra repayments without penalty, and many variable rate products include redraw facilities or offset accounts linked to your business transaction account. If your business generates irregular income or you plan to sell the property within a few years, a variable rate structure often makes more sense than locking in a fixed term.

The loan structure you choose should match your business growth plans, not just the interest rate on offer today. If you're buying the office building as a long-term base for your operations and want stable repayments, a fixed rate works. If you're buying as an investment with plans to sell or refinance within three years, a variable rate keeps your options open without triggering break costs.

Loan Amount and Deposit Requirements

Commercial lenders typically cap the loan amount at 65% to 70% of the property's value, though some will push to 80% if the property is in a prime location with strong tenancy. That means you need to fund 30% to 35% as a deposit, plus another 5% to 7% for stamp duty, legal fees, and other settlement costs. On a $1.5 million office building, you're looking at $450,000 to $525,000 in equity before borrowing costs.

If the building you're buying is owner-occupied and your business operates from the premises, some lenders treat the loan more favourably because they see the property as essential to your business operations. If you're buying as an investment to lease out, lenders focus more heavily on tenant quality and lease terms when deciding how much they'll lend.

We regularly see business owners try to fund the deposit by drawing equity from their residential property. That can work if your home loan serviceability supports it, but it also increases your personal exposure if the business hits a rough patch. Lenders assess the commercial loan and any associated residential borrowing together, so make sure your borrowing capacity for self employed income covers both.

Business Financial Statements and Documentation

Lenders want to see at least two years of business financial statements, including profit and loss statements, balance sheets, and tax returns. If your business structure runs through a company or trust, they'll also want details of directors, shareholders, and beneficiaries. Your accountant should prepare these documents to Australian Accounting Standards, and any unexplained variances between your financials and your BAS or tax lodgements will trigger questions.

A current cashflow forecast is also mandatory for most commercial lending. The forecast should cover at least 12 months and show how the business will service the new loan repayments alongside existing debt and operating expenses. If you're buying a tenanted building, include the rental income and factor in vacancy periods or lease expiry dates.

Some lenders will also ask for a business plan, particularly if you're buying the building to expand operations or consolidate multiple locations. The plan doesn't need to be a 50-page document, but it should explain why you're buying the property, how it supports business growth, and what happens if revenue drops or a tenant vacates. Lenders assess risk, and a clear plan that addresses downside scenarios makes their job easier and your application stronger. For business owners using non-standard income documentation, the principles overlap with low doc home loans, though commercial lending is generally less flexible on documentation requirements.

Flexible Repayment Options and Loan Terms

Commercial loans typically run over 10 to 20 years, with 15 years being common for owner-occupied office buildings. The loan term affects your repayment amount and how much interest you pay over the life of the loan, but it also affects how much flexibility you have to adapt the loan structure later. Shorter terms mean higher repayments but lower total interest, while longer terms reduce your monthly repayment and improve cashflow in the short term.

Some lenders offer flexible repayment options, including interest-only periods for the first one to five years. Interest-only repayments reduce your monthly outgoings during the early years of ownership, which can help if you're also funding fitout costs or dealing with vacancy periods. Once the interest-only period ends, repayments switch to principal and interest, and the repayment amount jumps.

A revolving line of credit or business line of credit structure can also work for commercial property purchases if you want the ability to draw down and repay funds as needed. This structure suits business owners who plan to develop or refurbish the building over time, as you can draw funds progressively rather than taking the full loan amount upfront. It also gives you access to working capital without needing a separate loan facility.

When Business Credit Score Affects Approval

Your business credit score matters, but it's not the only factor lenders assess. If your business has a history of missed payments, defaults, or court judgements, expect lenders to ask for explanations and potentially decline the application. A strong business credit score won't guarantee approval, but a poor score will almost certainly block it unless you can demonstrate the issues are resolved and your current cashflow is solid.

Lenders also check your personal credit file, especially if you're a director or sole trader. Defaults or judgements on your personal credit can affect your ability to secure commercial lending even if your business financials are sound. If you've had tax debt or ATO debt, lenders want to see payment arrangements in place and a history of meeting those commitments before they'll approve a commercial loan.

Fast Business Loans and Express Approval

Commercial lending doesn't move as quickly as residential lending, but some lenders offer express approval pathways if your financials are strong and the property is in a prime location. Fast business loans typically involve a streamlined assessment process, with conditional approval within a few days rather than a few weeks. Settlement still takes the usual 30 to 60 days, but knowing you have finance locked in early gives you more confidence at auction or when negotiating terms.

Express approval usually requires clean financials, a solid deposit, and a straightforward loan structure. If your application involves multiple entities, complex trust structures, or properties in regional areas, expect the process to take longer. Lenders move faster when the deal is straightforward and the risk is low.

For business owners who also need personal lending solutions, understanding how self employed home loan applications work can help you structure both your commercial and residential borrowing more effectively.

Call one of our team or book an appointment at a time that works for you. We'll review your business financials, work out how much you can borrow, and structure the loan to match how your business operates.

Frequently Asked Questions