The SFH and the 1b/1ba ADU are currently occupied by tenants under RSO and paying far below market rents.

I dont think you need advice for anyone how to structure this your already experienced operator.. the decisions is do you want to keep adding doors or concentrate on paying off what you have.

Even though I was cash challenged I held onto my house (putting past due payments on the backend) and had equity to sell, pay off debts, and get my credit in check.

I would get an engineer in there, get a quote on the work, and try to negotiate the seller to pay to get the work done

I just got off the phone with a seller who states that in a land contract, he would have to pay back up to 80% of payments to the buyer if the buyer defaults.

@Mark ShubinHouse hacking means buying a place and living in one part while renting out the rest to pay for the loan.

@Bethany Travis, the short and straightforward answer is to pay a real estate attorney to draft a purchase and sale agreement with an exhibit to assign the contract.

So I need to pay them off or keep them on the books and continue buying property with DSCR loans from now.  

In my own personal finances, I do work with a fee only advisor - I pay him a fixed fee out of my pocket based on net worth, and he doesn't collect anything for investment in particular funds, particular brokerages, financial products, etc.

If you buy at 373k, you're probably paying around 2,200 a month in mortgage.