We recently partnered for real estate investing, were under contract for a house flip but decided to walk away.We've done a thorough inspection of the "bones", tomorrow is really focusing on mechanicals, electrical, plumbing.

I pleaded that he will have an opportunity to make money on this fix and that if I don't pay, he can put a mechanical lien on the property and if everything works out, every project in his territory is his.

My father in law has owned a full service auto repair shop and used car dealership for 30 years.

Tenant agrees to not make alterations, changes or additions to plumbing fixtures, light fixtures, heating units, or locks.Tenant agrees to hold Landlord harmless for any mechanic’s liens or proceedings that result from Tenant actions.Any alterations or additions made by Tenant become the property of Landlord when Tenant vacates.

I know some good mechanics and I know some bad ones.

I don't.2) It's illegal in a lot of states to use a mechanical sander or grinder on lead paint.

Those things will go on forever and as @Jon Holdman says they are not mechanically complicated.

I have an auto fill ss that I can play with the numbers to make sure I am buying at the best price.

That is really a red herring any any scoring mechanism that gives people points for talking seed investors or venture capitalists into investing in them is flawed IMO.  

These will give you a good base of knowledge on strategies for financing deals and the mechanics behind what makes a successful deal.