The comparison you are actually up against
A buyer at this level has an option most buyers do not: build. When a home is priced within reach of new construction on a comparable parcel, every deferred item gets mentally costed against that alternative — and buyers are not generous in that arithmetic. A roof at the end of its life is not discounted at replacement cost; it is discounted at replacement cost plus the inconvenience.
This is why the usual "buyers will make it their own" reasoning fails here. It is true of cosmetic taste and false of condition. Buyers will happily change your paint. They will not happily inherit your twenty-year-old HVAC.
The dividing line is roughly this: fix what makes a buyer doubt the house. Leave what merely reflects your taste rather than theirs.
