I will say that the fact that hiring a PM would murder your numbers does make me a bit uncomfortable.

There will always be worries and concerns, but with a professional PM company in place managing them for you then you should be fine.

I would say let them apply and have them have a local professional fill out your form certifying that they require a service animal as allowed per your state regulations.

did you hire a property manager?

During the summers get hired as a labor with a general contractor then with a window company, a framing company and or concrete.

If you start seeing properties you like give some property managers a call to make sure you'd be able to have it professionally managed.If I had $80-120k waiting to be invested and lived in LA, NY, SF, etc.

I'm especially interested in someone with experience in 2-4 unit multifamily properties, but any tips on solid professionals with neighborhood experience would be great.Thanks! 

I am curious if we can get an actual professional legal opinion on this matter. 

You can look into other ways to accept online payments and talk to the tenants about using a different service that is more efficient.Talk to the tenant and calmly and professionally tell them the expectations: That the rent will be in your hands by whatever date, regardless of their delivery method.

Make sure to talk over the septic situation with them.As long as they are on-board then I'd hire an architect and bid it to a few contractors and see if it made financial sense.