@Lynnette E.I am married filing jointly.

Looking for a sample contract showing loan from private individual. Showing contingencies if project runs longer to flip than estimated, over runs etc.Any information would be greatly appreciated. Thanks

Currently running numbers today on a possible duplex in a college town that rents rooms individually with a joint liability in the common areas.

Here's why:(1) They have more income, and therefore have more room in their household budget to absorb an unexpected expense.(2)  They are are jointly/severally liable (under my lease, at least), thus they are all individually "on the hook" for the rent. 

Only concern I would have there is if the seller for some reason couldn’t pursue it (death, mental health issue etc), there must be some way for someone else involved to take over to make sure it happens.

I’ve already talked to planning & zoning & have the health department permit numbers.... waiting on a return call.

I have no overhead at the moment other than my cell phone, car insurance, gas, health insurance, etc. as I am currently living with my parents again.

Is their a per diem agreement for past due steps in the project (outside of any crazy weather, health issues, or stop work orders) These are just some basics.

I agree that separate LLC's are the way to go.I wouldn't have any ownership in my sister's property but I was considering a joint "Branding" that could benefit us both. 

I will add him to the lease and ensure the new lease states all are jointly and severely responsible for rents due.