Fixing a leaking faucet or toilet or changing out a broken ceiling fan would show goodwill in addition to keeping your new to you property in good order.

__________This toilet right here needs no caption.

I plan on spending some quality time on Home Depot/Lowes/Menards web sites to get cost or cost/square foot for various materials (drywall, toilets, various types of flooring, etc.) 

If you have older faucets, toilets, and shower heads, you may want to think about upgrading to low-flow fixtures. 

However with 10 units you have 10 HVAC systems, 10 water heaters, 10 sets of plumbing and electrical systems, 15-25 toilets, 3 roofs, etc= something will go wrong every year. 

Normal tenant issues: slow toilet, broken garbage disposal, broken electrical outlet, tile repair, etc. 

Instead of bidding "remodel bathroom" - get bid to install toilet. bid to install tub. flooring.Seems like getting 3 diiferent contractor bids really helps me understand what I want and then communicate it.

Be a bit more creative and let that old landlord stop fixing toilets!

Paint and prime cabinets inside and outReplace cabinet hardwareReplace existing vanity tops and replace with granite top, new sink and sink fixturesReplumb sink & sink fixture supply lines and drains if necessaryInstall new door hardwareInstall new doorInstall new toilet and toilet seatRefinish (not just spray) existing tub to whiteRetain existing wall mirrorReplace existing ceiling light and exhaust fan.

Your lease will impact these numbers as well, is your tenant responsible for basic things like toilets they clogged, light bulbs, etc.