Key exchange lock boxes for short term lease properties are often targeted by adversaries. A lock box code can be shared by a tenant with a 3rd party, the tenant themselves can use it again or the code can be brute forced by an unknown adversary.
To reduce the innate risks of a key exchange lock box its important that the pin is changed after every guest and if the property is left empty, the code should be changed at least weekly. Electronic monitoring of the lock box is also recommended. Monitoring can be done with CCTV, an electronic lock boxes code logging function or a combination of both.