Under $150, easy to install and use, tenant can set their own code but landlord can retain the master and always have access, tenant can't lock themselves out, standard key for emergency backup, batteries last a couple years, etc.

For a co-signor we require a full application, screening and 4x the rent

Similarly, is an appraisal required?

Quote from @Kmsuea Abdei: This used to be a state requirement, some states required it, and some brokerages required it.

Most municipalities require a contact and not the manager in the wording.

The CTA is reinstated, and we are back to being required to register.

CA rules do not require a closet but some jurisdictiins in CA require a closet.  

Fix and Flip -Requires a minimum down payment of 10% with 100% of the rehab financed. 

These are typically interest only and require a payment of 1-4 points up front depending on your area and the PML.

In many places you might be required to get some kind of municipal occupancy inspection.