The big problem is the costs taking to long to recover in many people's minds when contrasted to buying an existing community and either keeping it like it is, or upgrading it.I would never do rentals which is an opinion, but, an opinion of someone who has been doing this since 1975.

What are some good tenant-proofing upgrades that I can make before renting out a unit in my MF?

However, I am re-introducing myself because I recently went through a job change (a huge upgrade, I'll add) and moved from Pensacola, FL to Birmingham, AL.

The next thing i would look into is upgrading common area lighting to LED, this has saved nearly 30%.

Upgrade units that have carpet to wood flooring do basic cosmetics to units that need it, and build the 2 units in the empty basement.

That is a lot of why I upgraded to PRO. 

We once did a major upgrade on a 6 unit and because of the construction and change all of the tenants moved out on their own 1-2 per month.

I should confess that i didn't like that house, but i had to buy it to settle.I have even spent 25k on it for rehab, but still didn't like the building nor the neighborhood.Fast forward, i have broken up with my gf and haven't used the house for years, or event visited it.last summer, i thought of selling it, and i was surprised that i could easily sell it at 127k with 27k net profit.Why Am I sharing this now?

(I know I sound like a broken record, but you need to know your numbers).Good luck!!

You can always upgrade single items later if you feel you need to, you can't really downgrade...Also, have a plumber install your plumbing if you're worried about flooding...plumbing and electrical are risky to DIY.