Seek out a mentor who has invested in real estate to offer advice and encouragement.Determine your target market, available funding sources, and acceptable level of risk before formulating an investment plan.

Haven't made a decision yet to accept this offer

They accepted my offer so I am happy to have this confirmed ! 

For example, I mention that every adult must pay a $30 application fee, pass my credit/criminal background, make a combined income of 3x the rent, and whether or not the property accepts pets.

@Robert Ashton most of this is acceptable, although the "broad language" issue is up for interpretation as you haven't presented an example.

If you do it anyway, then you must accept that you will probably realize a loss because those people will not respect the time, money or effort you put into a rental property and will just think you're a greedy bastard. 

I have accepted an offer with a buydown and am in contract now and my response to my realtor about the offer was simply that I was wondering when that was going to happen.

After that I always cover that tenants will have to work with vendors for repairs and if they can't accept someone in their absence they have to arrange their schedule to meet the vendors, not the other way around.  

For example, if you file for eviction but accept a partial payment after issuing the eviction notice the judge is likely to take that as proof that you made a payment plan with the tenant to pay their outstanding balance and deny the eviction. 3.

A $25 increase is a bit more than nuisance but as long as it's in line with the market, you should get them to accept.