Much too difficult! 

@Vina Merrill,I don't have much intel on Knoxville, but I’m active as an investor, turnkey provider, and builder in Chattanooga.

If worse comes to worse and I need to get a judgement against the tenant and co-signer(s) can I force them to pay?!?

Unfortunately, this reassessment is unavoidable, so you’ll need to evaluate whether transferring the property is worth the potential tax increase.If a Transfer Is Not Feasible:If the potential property tax increase makes the transfer impractical, an alternative option is for your father-in-law to secure a Home Equity Line of Credit (HELOC) on the property.

I can into this at length so if you need more details let me know but for the sake of time - it's allowed.3.

. ($150k down, 5 year seller financing.) my point being you may get $20-$40k more in a year if you don’t need to sell. 

If this is for real, I strongly suspect you'll need to be an accredited investor.

@Lindsay Davis thank you so much for the advice!

@Jaycee Greene is pointing out that we need to be specific when we are planning to meet with people.

Unless the property needs work and the seller is desperate, you're not going to find a seller willing to do any sort of seller financing on their end.