You have to draw a line somewhere.I find timely fixes like paying extra to fix the heat on a Sunday in January endear you to a tenant more so that what shiny new object they can get. 

Heat pump units are more efficient than window or portable air conditioners, more aesthetically pleasing.

If you buy a fixer upper that looks pretty good but has old wiring, plumbing and heating you may be replacing everything anyway. 

Hi all,Recently purchased a multi and one of the first projects I’m planning is converting the property from oil to nat gas heating (there is nat gas going to the house already for water heaters).

if the numbers work it shouldn't be a deal breaker, get a mold abatement company In for quotes to remediate, plan on waterproofing the exterior basement walls and adding heat to the basement if you plan on doing anything with it

@Charlie Hyatt Roof, HVAC, plumbing, and electrical because we are adding electric heat to the 3rd floor.

Such conversion need not comply with the requirements of the following specific provisions of this chapter:(a) Section 13-196-660 (height limits); however, in frame buildings, four or more levels of living space shall be prohibited and in buildings of ordinary construction, with or without attic living space, five or more levels shall be prohibited; (b) Section 13-196-050; however, all dwelling units must comply with the exit provisions of Chapter 13-160 except basement dwelling units may have a second exit through a room containing a heating plant; (c) Section 13-196-670 (stairwell enclosures); (d) Section 13-196-680 (corridor enclosures); (e) Section 13-196-690 (dwelling separations); (f) Section 13-196-710 (basement ceiling construction); however, if the basement contains a dwelling unit the entire basement ceiling construction is to be wood lath and plaster of half hour construction; (h) Section 13-196-720 (heating plants); however, basement apartments are to be separated from heating plants with partitions of one hour construction.

In this heated market, you might not have motivated sellers i.e. low chance of getting better seller-finance terms. 

But I'm not an inspector.It's a cape and the second floor isn't heated and is used for storage.

The market is heating up but there are still cash flowing deals out there!