I am looking for a solution to a key fob entry for my apartment building.  We run several Airbnb units and the building requires a key fob for entry (we use smart locks for the units).  I am trying to find a smart lockbox (10-30 boxes) which will generate limited time codes (either time frame or can be used only twice).  Does anyone have a solution that has worked for them?  We would want the ability for permanent codes as well (owners / cleaning service to verify fobs returned).  Something similar to "latch" locks for a lockbox would be perfect.  Prefer integration with airbnb automation software as well.