Price per sq ft is not the way to put a value on a property. You need to have your agent do a market analysis of properties similar to the one you are interested in to figure out the actual value of the property. If your agent is not supplying you with the sold comps then find another agent. this is not a decision to be made with wrong info.
If you can give me some more details as to where you are looking I'm more than happy to help.
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