I would think in AZ that is a must, because summer heat and AC must run 24 hours a day.   

My brother's rental is a little over 1,000s sqft heated living area, so the ADU would only be permitted for 500 sqft in Winston-Salem, according to information I found online .One advantage of an ADU I believe would be the ability to hook up to the primary residence's utilities. 

I am just left with heat water garbage and all the incedentals How did you find this deal and how did you negotiate it?

As you all know, getting a phone call in the middle of the night from a tenant with no heat or water leaking is a nightmare most do not want.  

We feel very confident in our underwriting, but given the jump that we made from SFH to an apartment building, we want to ensure we're not missing steps in our DD/inspection plan.Here's our current plan:1) Have a general inspector complete a Property Condition Assessment.2) Have specialists complete an evaluation of the roof, electrical, foundation, and heat source (2 steam boilers).3) Review financials, all leases, existing service contracts, rent roll, tax assessment, rental certificate, and 12 months of work orders.Here's what I'm not sure about:1) Are there DD items (specifically those that we would request from the seller) that are not captured within #3 above that we should be requesting?

Property management is a pretty painful industry similar to general contracting... no one ever calls to tell you how grateful they are that the heat is working lolHere in Illinois, the answer is yes or you at least need to have a managing broker on your team as JW mentioned above. 

We also had an iron tub in the front yard that my mom would fill with water and put black plastic over to help warm the water, then a little hot water from the wood stove, and we would take turns bathing in the great outdoors.Rough stuff, but I don't recall ever being unhappy at that time. my Wife Grew up on Puget Island under the same circumstances.. no hot water had to heat on stove and then fill bath out house etc.

Moving in 4 years and not sure if I should just reline the flue and hope the furnace lasts until we sell; bite the bullet and replace the furnace with a heat pump; or reline the flue and replace with another oil furnace.

Plus, we didn't budget for furnishing the personal care home, or the the cost of appliances and air and heating. 

I had him give me bids for some other jobs but after my bad experience with him and a heated argument, I told him to forget about the other projects and just finish up the doors and be on his way.It was stressful for me, but what helps balance it is to remember that YOU are in charge.