I am looking for smoking inside, making sure the electrical outlets are covered, dripping faucets among others.

Make it part of your system to do an inspection every 6 months, where you check smoke detector batteries, filter, check for leaks, running toilets, etc.But, no, the appliances are your responsibility, unless you have a lease and state laws that allow you to make the tenant responsible.  

A is solo, recent law school grad, no pets, no smoke - but makes $200 less than the 3x rent rule.B is solo, no smoke, makes plenty of $$ - but has 2 labradors (sometimes).

Check to make sure all the smoke detectors and CO detectors are working.

There are exceptions to every rule except 1: Where there's smoke, there's fire.I would think that the kind of person/people you want in your rentals doesn't/don't: 1.

I do have specific language about them being responsible for plumbing issues, not going on the roof, maintaining the yard, maintaining smoke/carbon detectors, etc, etc. 

These are generally around credit, criminal, and evictions but could expand for instance to your pet policy and or smoking etc..  

But, she also expected me to find out who was smoking when she thought she smelled smoke.  

One of my SFH renters called me this morning to let me know they had called the fire department because they noticed smoke coming from a vent.  

A few other items in my lease include a no smoking clause, a cancellation clause, and a few more that don't come to mind right now.