small property owners do

Would you give your car to a complete stranger? Of course not. But landlords give keys to their
buildings (which are worth much more than any car) to complete strangers. Consider what typically happens when a landlord has an apartment for rent. The prospective tenant calls and makes an inquiry about the apartment. The landlord is so happy to get a call he spills his guts to the tenant, and makes an appointment for the prospect to see the apartment.
The prospect comes over and the landlord shows the apartment, all the while telling the prospect how wonderful the apartment is. At that point, if the prospect says he wants the apartment and has the money, the landlord is so mesmerized by the cash that he will give the prospect the keys on the spot.
What does this landlord know about the prospect? Nothing! This prospect could be New York's number one deadbeat. He could be wanted in a dozen states for murder. Yet the landlord just gave keys to property worth more than $50,000 (and often much more) to him.
Landlords Don't Get Rental Applications From Prospective Tenants
The landlord-tenant relationship is a very odd one. The landlord is at the most powerful BEFORE the tenant is given the keys. Once the tenant has the keys, then the power shifts to the tenant. The tenant then has a right to be on the property (whether or not he pays the rent) and the police will enforce that right.
After the prospect has seen the apartment and has said he wants it, that is the point of the landlord's maximum power in the relationship. The prospect needs the landlord to agree to the tenancy. Therefore, the landlord can get anything he wants out of the tenant at that moment, but not later.
That's when the landlord should give the prospect a rental application. Some owners make up their own (this can be very dangerous unless you know what questions you cannot ask), while others simply buy rental applications from stationery stores.
A rental application has two purposes. The first purpose is to find out who this prospective tenant really is. The second purpose is to get enough information so you can find him later if he leaves town owing you rent. Applications vary, but you must get certain basic information: the full legal name of the tenant, current address, prior address, social security number and date of birth. It's highly advisable to get the tenant's occupation, employer's name, driver's license number, car license plate number and bank.