I swear, 99% of unnecessary maintenance problems/calls were from a tenant who had a mess and flood in the bathroom because they didn't have a plunger handy.And be sure to let them know that there is no such thing as a "flushable" anything.  

I'm not saying you can't do your method and make it work, just that it is unnecessary and perhaps more work.

17 years working with property management companies.  1 exactly as @SueKelly describes, their entire profit model was based upon charging huge fees every month on minor and unnecessary maintenance expenses. 

Additionally and in the alternative it was unnecessary for the landlord and/or his agent to make a house call to procure payment and the tenant is not liable for consequent costs arising. 

They pay rent on time, take care of the place, follow the terms of the rental agreement, and don't cause unnecessary drama.

This only causes you unnecessary work and "muddies the waters" legally.

The tenant will need to follow all of the laws about running that business and there can not be an unnecessary burden on the landlord. 

I don't see a way of figuring this out and worrying about it would bring on unnecessary stress.

Don't start doing unnecessary things for a high-maintenance tenant, because they'll just keep you hopping. 

You could just say you can't afford these kinds of things that you believe are unnecessary, but you can see it's very important to the tenant.