How do you (yes you individually) determine property value?

[Mike Ventura]

Easy question right? I can’t wrap my head around it. I’m trying to line up my next deal but I don’t know how to value the property. It’s unique - listed as a single family but used to be a B&B. Now the units are rented out individually. Gross income would be 6500-7000 with last unit rented out. Current owner lives in it. My goal is to purchase with hard money. Only issue is I don’t know how to value the property. Which then presents an issue when I refinance out of the hard money 1yr term. It was listed at 545k. - Zillow, Realtor, Trulia all have the property in the 375k-400k range - town assessor has it at 500k (last assessed 2001). I called him and he said properties are selling for 10-20% over their assessment. - listed at 545k Bottom line there is a huge spread.. I’m stuck! Any recommendations on how to arrive at a valuation? Thanks!