As we mentioned last week, information on what to/not to upgrade in your home is often contradictory. A recent review of national surveys on the topic showed contradiction on what improvements to make of up to 75% difference. Frankly, with that being the case, I won't bother to share any of these "studies" with you, and only give you advice from years of seeing homes flipped, and what made the real difference.
Chipping/Peeling/Old Paint
This is a low cost, low skill project that can revitalize a home. Additionally, if you cure paint issue, you will open up your home to be able to receive FHA/USDA/VA finance offers.
Updated Kitchen and Baths
Does you kitchen/bath look like its from this decade? If so, leave it alone. If not, you might consider if partial updates (counters, paint, fixtures) might bring it into the decade.
Air Conditioning
We live in Virginia, and summers are long and hot. This is an expected amenity, and your days on market will be less if your home has AC.
Obvious Deferred Maintenance
Does your home "obviously" need a new roof - then get it done. Was the furnace "obviously" installed in 1950 - then get a replacement. Anything that makes a potential buyer say, "I don't want to have to deal with that," is a likely candidate for updating and replacement.
Will these improvements make me money? If you're hiring a contractor, no. However, any of the work that you can do, may net you a return on your investment.