So how do you factor in this additional risk or cushion for the 'unknown'?

unknown authorAlso, "Reality is merely an illusion, albeit a very persistent one."  

You are so right about the unknown..

But as 1st position despite the unknowns you are in a good position.

There are just too many unknowns and investing in a town with a population of 600 is just risky. 

Rehab Costs - $20,000.00Although flooring, paint and countertops won’t cost $20,000.00, from the pictures it seems some of the meters may have been stolen, so I am concerned that copper thieves may have gotten to it, so this accounts for unknown costs.

It would allow me to get a new residence quicker but at some unknown possible expense.3.

The other had an unknown tenant so I had to evict them.

I'm not sure if I should be mad or thankul... theres smething special about this house, but it is a MAJOR project with a lot of unknowns.

@Mike M.I understand but the house was built in 2015 so renovations will be to a minimum and the first thing I tell a seller is that a contract will be involve between both the seller and myself and the buyer and myself and also in the contract that I have I make sure the seller knows that if there are any unknown liens or taxes on the property, that may prolong the situation outside of the deadline that was giving.