Remote Keyless Locks For Student Rentals, out of state?

[Eddie Starr]

I was looking around through the forums, and reading some feedback for keyless locks, that can be accessed remotely. 

The ERLs seem like they would be my best bet, especially since I don't want to be stuck if there's a wifi problem. I would want to be able to change the lock code remotely (web/mobile). Anything similar, that's a lower price? Also, on occasions when power may go out (for this, or others), are there "fail safes?"

Also, looking at out of state student rentals, and was wondering how would handling the locks work? Would I have the realtor, cleaning company, or a contractor install it (and pay them a small fee for it, maybe)? Since the battery life is, in the ERL case, for 3 years, should I then have the cleaning service put in the new battery?

Thanks.