You don't want to get sued for injuries on the job because the contractor picked up some random guy at Home Depot and he's not covered under any workers comp. insurance.

Some purchase and sales agreements (Lease Purchase) may have specific performance requirements that allows litigation is the buyer doesn't buy, but I don't really recommend adding insult to injury if a buyer doesn't close in a lease purchase by them forfeiting their earnest money AND staring down the barrel of a lawsuit for not buying.

I understand that this should generally get passed on to the tenant via annual rent raises, but there are other implications of doing so that could add insult to injury.  

Land minds such as aesbestos, OSHA safety rules, injuries, and lead based paint. 

As long as the asset is still generating income and no catastrophic financial injury has occurred, then renewals is an easy process, with my bank that is.

Repetitive strain injuries from typing so much have led me to realize that coding is a young (wo)man's game.  

Aside from the fines, you don't want to have to live with the consequences of a death or serious injury on your project because someone gets hurt doing something stupid and you didn't know what to do.Also, how are you going to pull permits without someone being licensed?  

Think like an estate planner: what happens if the seller dies, get incapacitated due to illness or injury,  dies without a will ?

I would call that middle class at least, and that's assuming 0% interest on that initial $3.5M.So, you're ***-u-me-ing perfect health, no injuries / accidents, no natural catastrophes (hurricanes / cyclones, wild fires, volcanic eruptions, ... at least two of which are common in HI), vehicles which last forever and never need to be replaced, destruction-proof housing and furnishings, ...... and if you CAN live that lifestyle in HI on $100K / yr (most people can't in ANY state), why are you not teaching personal finance at the university level? 

If a fire caused any injuries you may find yourself in a world of hurt.