Home buyers walk too frequently.  

@Daryl Jarrett , the credit system most frequently used is FICO, which runs from 300 to 850.

In my county, the deeds database is frequently updated, enough so that you can time your letter to within a day or two of the notice and get ahead of the rush.

Now you can argue class A's might have some basket cases too and that's absolutely true, but it certainly is a lot less frequent and a lot easier than class C.You are hopping a bit all over the place on strategy as well.

The advantages of this would be the option to do BPOs and the possibility for more frequent transactions.

This may not be true in your case but is true frequently in my experience.

You will frequently be forced to evict (or foreclose) on the person and you'll find out that there is a bunch of deferred and/or botched maintenance.

I called the previous landlord and they said that the tenant keeps the house in good shape, but is late 1 to 2 months rent fairly frequently. 

I would not like them mailing me a check as I travel frequently and it would delay funds to have to deposit after it's mailed (usually after post office delivers held mail).

I see this frequently in my market - homes are listed on the MLS at fire-sale prices - as short-sales, and three minutes after posting, they're switched to "pending" status.