Many times I experience trouble with remote key as they require new battery every few weeks.

Remotelocks.com to monitor locks, battery level, and update entry codes.

That's just to break even and it doesn't take into consideration maintenance, battery replacement, and other issues that can change during that time.Solar power is to help people feel good about their environmental footprint and is not what I consider a good investment.

We manage a handful of properties remotely (however most of ours are local to Charlotte market) and we keep actual keys in a lockbox in case batteries die or any malfunction.

(full solar, battery bank, water tanks, etc).

Then I will need to ride one of my jet skis to make sure the batteries stay charged up.

https://www.courier-journal.co...

We equip all of our units with 10 year lithium battery smoke/CO combo detectors in the hall outside the bedrooms.  

They have loads of training modules available, the mentoring program is good - make sure you are placed with a local mentor that understands your local rules and regs. 

No more, the Verizon boxes have notes on them, do not install BU battery.