Ask your Realtor what the commission rate on a particular home sale will be. For instance, suppose the commission rate is 4.5 percent. Divide the percentage by 100 to obtain the decimal form that you will use later in the calculation. For example, 4.5 / 100 = 0.045.
Consider the likely sales price of the home you are buying or selling. If the deal is final, you will know the actual price. For instance, consider a house that is likely to sell for $250,000.
Multiply the sales price of the home by the decimal form of the commission rate to calculate the Realtor fee:
Realtor fees = 0.045 x $250,000 = $11,250