Noisewise an overnight caregiver also has to be quiet enough for him to sleep.

Sleeping on the couch is never ideal - regardless of ROI.Having said that; I think you are already doing a marvelous job at garnering spousal support.

In my opinion I have three options and hoping you pros have some great ideas:1) Hiring a professional commercial boiler expert to thoroughly clean the boiler and go through the whole system with a fine tooth comb.2) Do the HVAC conversion in the soon to be 4 empty units and keep the boiler working for the remaining occupied 3 units. 3) Do the HVAC conversion in each unit one at a time and when I get to the units that are occupied I'd offer them the other units to sleep in or perhaps rent them a temporary place to live. 

Going in your sleep .. the resale on them is not the greatest but if you got them cheap enough and the proper steps are taken to secure the ground buy pinning it or the other way .. i cant remember right now .. either way .. i wouldn't recommend it for anyone but a seasoned investor .. cape coral has a ton of duplexes .. you may want to watch the auctions ... daytona and deltona has some by the beach that are grandfathered in .. and they arent to bad in price considering you can rent one side or the back house or a converted garage for a few months during spring break and bike week and daytona 500 .. you can make more during those times than renting it yearly .. plus if your living on site then you can watch who you rent to mire carefully .. anyway .. i hope i gave some insight .. hope to see you in Florida soon .. 

Traditional reading puts me to sleep when I do too much of it all at once. 

At this point in my life I've come to a realization, that If you want to be a successful person, you must exhibit successful habits and behaviors, I am going to work to being more disciplined than I've ever been from budgeting money to Time Management and better sleep and fitness/nutrition habits.

I actually took the unusual step of agreeing that we owed her (we probably do) and it would be worth the sleep at night to feel like I did right by her and offered her an additional $800.

Also, sleep in on weekends.

You will sleep a lot easier at night.

Depending on your market, you can optionally list that property as "occupied, instant cash flow, investors only, please do not disturb the tenant."