She is an architect and GC (along with her husband) and knows all the people at the City for permitting. 

Building would be worth upwards of 20mill + 2. the property i own that is in the middle and the best lot for the project used to have a house on it, but we demolished that and it is only land value now.. practically free and clear.. banks i've spoken with will not loan me money on the land. 3. the costs to get the plans can't cost too much considering the value of the project... not trying to update anything, but want to tear down and either build or sell. 4. plans and permits could take 3-6mo ?

Are there online legal sites/apps that you can pay for this type of service?

I have the architectural and engineering plans already paid for and was looking to get the permits to start building.

If you've got enough damage to bring the price down that low, then it is a major job, and the permitting/paperwork/inspections needed to get it back up and running could be the biggest hurtle. 

Unless, of course, the offer is not legally binding.

What recourse do I legally have?

Rentals are permitted.

Otherwise you wouldn’t be writing about it here).From a legal perspective, are there ramifications from NOT kicking them out?

Aside from the immense guilt, you could face major legal problems.