My FIL owns several properties, you should hear the complaints, its almost humorous. All of his properties are low rent apartment houses.
Your FIL is what is known as a 'slum landlord'. He has problems with tenants for a couple of reasons.
1) His rentals are in an area that doesn't offer much other than low rents. He has nothing to attract 'desireable' tenants.
2) Therefore, his 'prescreening' methods have to be especially stringent. You can eliminate 95% of tenant problems with proper prescreening and move in procedures.
a) Require that income (verified) be a minimum multiple of rent (about 3x).
b) Run a credit report to: verify previous addresses, especially those not disclosed on the rental application; determine if there are any liens or judgements which may affect the ability to pay rent; and verify employment.
c) Get a substantial (or what the market will bear) security deposit, up front, in cash before move in.
d) Do a move in walkthrough checklist. Go through the rental with the tenant, making note of any defects, damage, stains, missing screens, etc. This will be compare to the condition at move out and provides a basis for withholding the security deposit.
e) Execute a comprehensive rental agreement that is up to date and consistent with your state law. Don't use something off the shelf from the stationery store.
f) Be strict about rent collection. If rent is not on time, immediately serve the 3 day notice (or whatever document is appropriate in your state). Don't make verbal deals for payments; you wind up legally altering/voiding the original agreement and losing your rights.
I professionally and successfully managed rental properties for several years. Even those in 'low rent' areas can be run efficiently, and provide a good return for their owners.