This can be a fun thing or a disaster. Renovating a rental is a very fine balancing act.
Putting Italian marble tiles in the entrance way will look fabulous, however your tenant won’t thank you, won’t pay any more in rent, and probably won’t care. So I guess don’t do it.
To do this successfully you need to do a complete scope of works and get this priced.
If it’s going to be major, for example, re-doing kitchens, bathrooms, etc, it may pay once you have your scope of works, to get a valuer to help you.
Spending a few hundred dollars with a valuer to do a now and after valuation may save you thousands of wasted dollars, and also give you a sensible budget to work to.
DIY on every piece of the puzzle is not always the best thing because if you pay peanuts you get monkeys.