I hadn't thought about you solution.

Good afternoon BP nation,      I always seem to have common items stolen from every rental unit when tenants move out. I tend to see stolen light bulbs, smoke detectors, hydraulic door closers (yes), shower curtains a...

A security check a pest control treatment and a through cleaning is around $350.

.- He has now given me the ultimatum  of either me and him finding a solution that is  "fair to both of us" or I move out.

Prevention is preferable over solution.

https://moneyinc.com/the-top-five-ibuyers-in-the-real-estate-industry/I was also going to suggest, as a potential interim solution to help you and your partner on the carrying cost, is to explore short term rental. 

I feel like I'm one of those people that's just "buying something" to get started.See the brief numbers below:Original Scope Cost NotesDemolition Labor Cost $4,250.00 QuotedConstruction Labor Cost $15,710.00 QuotedMaterial Cost $12,805.00 Ref - Home DepotPermitting/Fees $2,500.00 Ref - Development Services (estimated)Additional Scope Cost NotesSubterranean Termite Treatment $1,021.88 QuotedDry Wood Termite Fumigation $2,659.81 QuotedCarpenter Bee Treatment $161.29 QuotedReplace Misc.

I believe you will find a solution. 

Wood bleach is a peroxide solution applied directly to the sanded stain.

Everyone will say watch out for triggering the Due on Sale clause, but that is so rare, and as you have already alluded to, the solution is just refinance.