Probably only cost $30-50 to get an estimate.

Here in the same county, a friend of mine had an large, older ranch home, built in the 50's, on a gorgeous piece of riverfront property (in a very desirable, upscale, neighborhood), that still had the original electrical meter , and the power cable /electrical feed coming into the house right next to the front door!!!

Further, with the hot construction market, your bids will be almost assuredly be exorbitant.I think you already have the right thinking on renting the property out given Berkeley's insane rent control rules.

Next use the 70% rule to determine your allowable cost basis

You might be the exception to the rule, but there's always the question of whether you're leaving money on the table.Put it another way.  

Go on the MLS or even Zillow/realtor and go analyze 50 deals.

I'd be surprised if there weren't a "grandfather clause" allowing you to change your occupancy rules without evicting the existing tenant.

Hi Jane,The rule of thumb, if you want to make money, is that you rent should be 1% of the purchase price.Meaning if you are buying 150K property you want to be able to rent it for $1500. 

Each bank will have different rules, since each bank manages their money slightly different, so do try to get 3 sets of numbers from 3 different lenders to compare.2. 

You can get exception if the property was recently acquired although this rule is going to change pretty soon.