To build a real estate property pro forma for a commercial building you need to make assumptions. These assumptions are needed to project your property’s cash flows going forward. You may even need to use assumptions to get your property’s current operating budget since you may not have exact budget numbers if your prospective property is not listed with a broker for sale. Without understanding the current operating budget, you need to use assumptions to calculate your property’s cash flows today, after which you use more assumptions to project your property’s cash flows in the foreseeable future.

To be able to start your pro forma, you simply must input or calculate your property’s Net Operating Income (NOI), which is the property’s operating income minus operating expenses. If you do not have exact figures for the property’s operating income and expenses, which is the situation for many real estate property deals, you will have to estimate them using assumptions determined by market information and standards. Solid, realistic assumptions need to be the foundations of your good real estate pro forma. The most typical assumptions you will need to generate NOI are rental rates, expenses rates and vacancy rates.

For rental rates and vacancy rates, you should use the industry average rental rate for similar buildings in your market area, usually quoted as dollars per net square foot for rental rates and a percentage for vacancy rates. For expense rates, you should estimate the total annual operating expenses, usually in dollars per net square foot ($/NSF). These are expenses necessary to operate the property such as electric, water, landscaping, maintenance, etc., as well as taxes and insurance. Each industry sector and lease deal will have different assumptions for this expense. For example, retail and industrial leases are typically triple net (NNN), meaning the tenant pays all operating expenses; therefore, this assumption would be close to zero. If your property is an office building, you should assume you will need to pay a portion of the operating expenses.

When you have generated your property’s current NOI, then you’re able to use assumptions to project cash flows in the future. This is usually done while using the inflation assumption. Inflation is the assumed rate where a cash flow will grow as time passes. It is typical inside a property deal to assume inflation of NOI will probably be generally near the CPI (Consumer Price Index), or the general inflation or your overall market. If your inflation assumption is too high, the compound effect will greatly exaggerate your future cash flows and give you an incorrect valuation of your asset’s future value. It is vital never to over-estimate your inflation assumption.

When your assumptions are input and your pro forma is built, it is very important to run sensitivity analysis on your entire pro forma and assumptions. Sensitivity analysis is performed by changing each assumption and finding out how those changes in each assumption affect your pro forma outputs, such as IRR and NPV. Sensitivity analysis can help to target the assumptions which are critical to your pro forma.

For more info and tips on building real estate pro forma models and excel templates, please check out the Pro Forma GURU: Guide for Real Estate Investing at www.ProFormaGURU