Or they might be more likely to call you when there is a drip beneath the sink, rather than wait six months until the sink cabinet base has turned to mush.

For one, it's usually a bad idea to let tenants do any maintenance themselves, and you're basically telling them they have permission to do so.Plus, they just won't tell you about minor problems that could create big problems - like a leak under a sink, etc.  

If something needs to be looked at, I do a quick one-over look while I'm there - mostly checking HVAC filter, floors, and under sinks for leaks.

Replacing particle wood under the kitchen sink that the tenant claims is moldy...

So no kitchen sink or lower cabinets either. 

If the garbage disposer is backing up into the dishwasher, then the dishwasher line isn't routed per installation instructions as it's supposed to have a high point above the drain pipe level of the sink.

He was supposed to return Sunday morning to do that but he told her how to turn the water back on at the shut off valve under the sink. 

South of Boston we can get high efficiency FHW units installed for much less than the "new heating systems will sink you $10k and wipe you out" scare tactic excuse people use for not investing, not sure how that cost translates to NY.  

I leave a package of soap in each dish in the bathroom tubs and sinks (or if there are soap dispensers make sure these are filled) and leave a small bottle of dish washing liquid by kitchen sink/small box of those dishwasher pellets in rental properties with dishwashers.

Hopefully not down the kitchen sink?