So the site owner has decided that commerce of virtually any type - including bartering or giving things away for some other consideration - needs to happen in the Marketplace. 

I rent upstairs for 750$ and downstairs unit at $850, rent includes water.

It needs about 30k of work, can probably make at least 50k on the back end (not including interest from loan) so lets say 25-35k with minimal work.

It is written by attorneys and includes the law, not just opinion.

Fence repair, yard repair and mowing when its empty, siding and all exterior coverage, and it includes your insurance.  

If you can, itemize what you can- Does this include repairs from an inspection, or just what you can see? 

Extended periods of intense work can have negative effects on your productivity, including burnout.

If you can make a little extra of the financing thats great, but it doesn't make sense to me to include it in the valuation a property.

I will assume your cash flow projections are good and include cap ex, maintenance, vacancies, PM fees, miscellaneous, etc.Selling gets you virtually $0 so in effect you have $0 invested. 

Numbers that I'd be interested in seeing over time include: number of these built in your area you're evaluating, the vacancy rate, and how many units have been abandoned (in current state but also over time).