Very common for the lockout policy to be outlined in the lease.

If you don't have it already, I would put together a written Applicant Screening Criteria document that outlines what you are reviewing and your criteria (e.g. 3x rent in gross monthly income, NO evictions, etc.). 

Consider yourself extremely lucky.If you want a crash course in wholesaling, which is sounds like you need, there's a short book that outlines the whole process.

Does anyone have a guide on this subject?

Think, subject-to, master lease, seller financing etc.

I just wanted to find out from some other home owners that have used this or lenders that support it what's the catch or details outlining what the state the house needs to be in and what is supported by this.I feel i have enough funds to support a decent renovation on this house out of pocket.

What I have outlined here is precisely how I made the transition from SFH's to Multifamily. 

I would buy the homes subject to the existing financing.

Your contract should have an inspection period in it that will specifically outline what inspections you are doing and how long you have to complete them.

I am trying to calculate how seller financing would be a benefit to a seller as well as me the buyer and a good document that simply outlines the advantages to a seller to do seller financing.Does anybody have a good spreadsheet to calculate seller financing and or a good document that outlines the advantages of seller financing for a seller?