All of his items were removed, but he didn't clean out the fridge, bathroom tub/toilet were disgusting and full of filth and hair.

You would be surprised what comes your way:  "my kid flushed something down the toilet" (that's on them)/"I have no idea how the door came off the hinges" (that's on them) / "The sink is clogged" (they used it, they clogged it - you know the drill by now). 

You might not be swinging a hammer or fixing a toilet but don't be fooled that finding financing, arranging loans, looking for deals, and all the rest of it is any less time intensive.

I have made most of repair/replacement such as: install new toilet flapper at multiple toilets, repair stuck window blind that never been fixed since she moved in, replace multiple Closets door ball catch that stuck, blocked Dishwasher air gap valve due to build up dirt from dishwasher. 

Tell your tenants that no personal items go down the toilet or they will be billed to unclog any obstructions.

but I may change my mind if they pay me $1M/toilet... right?

She is asking if she can install handicap grab bars by the toilet and in the bathtub / shower for her mom.

How much for the pots and pans to go with.

You want to stop the door, not slam it into the wall.Sink cabinet drip pans are a plus.As you replace window screens, try to use a tougher material to withstand abuse.

You are much better off, especially if your units are above other owner units, to be pre-emptive in addressing the issue properly by a complete gut and redo of the bathroom fixtures (including tub OR shower pans), piping, waterproofing of surrounds and pans, and finishes that are current without being too "niche".Keep in mind that any "partial" update, where maybe you choose between doing the kitchen OR the bathroom; or only some of the flooring, will not only limit your rent increase and tenant pool, but you will likely never reach full market value (rent or sales).