If you do go with a non-connected lock please change the codes often, I often compare it to a hotel in that if the front desk told me the previous occupant's keys still worked during my stay I'd be sort of annoyed.FWIW, we use ResortLock from Lockstate (no affiliation, just what we use) on all our properties. 

The key is finding quality notes that are held by folks that are motivated to sell because they need cash.

You could always use those to prove they were smoking up; with that proof you can either move to evict or simply hold security and at least have some sort of proof.If you install a marijuana smoke detector I wouldn't even tell them what it is (aside from a smoke detector) as they might try and disable it.

We need people can not SOLVE PROBLEMS and that are PERSISTENTLY MOTIVATED.  

Thankfully I think that "click bait" of sorts is quieting down a bit. 

But you might be able to work out some sort of agreement with a tenant to fill that role for a slight rent reduction.

I have a tenant who’s also a property manager of sorts for me.

I want to ensure that I follow any sort of regulations and safety standards but I don't know where to even start or know how to estimate rough costs.

The walls on the second floor show white chalking and also some sort of drip marks.

If they're motivated to close the deal, they may come to the table.