Since this is a commercial stand alone building, it would be hard to have comparables, it is a closed down burger king. we have 2 fast-casual dining restaurant that are currently leasing, this is the first purchase. Thank for your response
Have you talked with the realtor representing the property? Often times you can ask them flat out, "What is the rock-bottom price for this property?". You can also bid below their "rock bottom".
You might also consider hiring a Licensed Commercial Real Estate Appraiser. Since they'll be working on your behalf, you can feel more comfortable with the estimate. You can click here for a list of appraisers in your city. Or, you can try a Google search with the name of your city followed by "Commercial Real Estate Appraiser". For example "Denver Commercial Real Estate Appraiser".
Comparable sales are available for commercial as well as residential properties. You could also do a replacement cost analysis. Just as important as a good appraisal is a good property inspection - especially if it has ben shut down.
You will need the roof, ac/heating, plumbing, and electrical thoroughly examined.