You might find that installing a mini-split system, properly insulating, and ensuring the finishes match the main home’s quality will make a difference in how the appraiser views it.

I would find someone that can demonstrate that the pipes were properly insulated etc. did they say why they wouldn’t cover the chair?

Energy Efficiency ImprovementsInstalling energy-efficient windows, doors, insulation, and HVAC systems can appeal to modern buyers who want to reduce utility bills.

You can only use a handyman for jobs under $500 as I recall....which will exclude tile, drywall, insulation, paint and well pretty much everything.... 

Quote from @JD Martin: I can't speak to rates - I think eventually they come down out of sheer necessity - but as far as the economy we must be living in an insulated bubble up here in Northeast Tennessee; no one has bothered telling us the economy is bad.

You have to consider insulation and heating/cooling too.

You'll definitely get the long term appreciation in the San Diego market since our supply levels remain low which helps to insulate our market here, but it will be hard to cash flow on immediately unless you use one of the above strategies I mentioned. 

If the home is 100 yrs old, I'm assuming it's a definite gut which is going to require new plumbing, electrical, heating, cosmetics.I spent about $140K reno on my multi family in the heights on NY ave and there were massive problems with it but it was a gut to 3 units & adding 2 bathrooms, 3 brand new kitchens 4 bathroom reno in total, all new flooring, sheetrock , insulation, framing, doors, electrical, plumbing, paint, parts of roof etc.

I ended up spending some extra time making the finished basement legal (add insulation and egress).   

You can look at a mobile home and see it as an easy rental with new carpet, trim and some paint but there are other bigger uglier expenses that can come up.Roof Replacement, soft floors (water damage) in kitchens and bathrooms- most floors are particle board, exterior door replacement (special order), underbelly insulation falling, bad hot water tanks with rotten floor underneath (real joy), bad windows (water again), bad bloated siding (water), water damaged base frame around perimeter of home, cracked tubs (special orders) and frozen pipes (Good luck finding a plumber to come work on a mobile home- they do not exist).