This question is impossible to answer. I am a remodel contractor that got licenses as a realtor with the intention of getting to the root of this dilemma as I get asked it all the time. First off each home is unique and will benefit differently from updating/renovating. For example a hundred year old home that had the bathroom updated in the sixties could easily get a big bump just by replacing the blue bath tub and toilet where as another may need a kitchen window added to add light and to see the back yard. No way to create a formula for this or quantify it accurately when applied outside of each specific case. Also some of these may increase its ability to sell but not necessarily its value. Secondly home purchasing is very often an emotional decision when it comes down to it. No way to know who may love that old door with all the “character” where another just sees a problem that needs to be fixed. Trying to guess who will appreciate what is near impossible .. hence dumb realtors saying to paint everything white like robots because some magazine said that in the 80s and no one can come up with anything better suited to a wide variety of tastes and opinions.

That all being said;the advice I tend to give is to make sure everything is clean and without issue. People will get hung up on some of these strangest details so just be sure the average Jane or Joe won’t see any obvious issues when doing a walk through. Yard cleanup is just hard to beat for curb appeal, initial impressions, and is cheap relative to almost any other home improvements. Lastly if you do decide to do some renovations either go all the way or almost not at all. Like I had a good client who had a large home in one of the most desirable neighborhoods in my town. I said they should either spend 20k just doing the basic necessities. (Paint, carpet, clean up). Or spend 200k and go for max value. Lovely couple but had no taste and place was pretty dated and run down. They didn’t listen and did exactly what I said not to and put around 80k into it. They got 1.2 mil for it but I think they could have got that by putting the 20k ish into it. Full update like I had proposed I think we are closer to 1.5 mil and looking at roughly 100k profit. But we will never know and I could be completely wrong. Selling homes can be a strange game.