With the frequency of moves and the little/no money down you put into a VA loan, after you calculate for insurance, mortgage and maintenance / repair funds, I found that a PM would roughly cut my cash flow by about a third to a half.  

I know this depends on what lists and frequency of mailing.

The probability of getting a positive ROI on direct mail will depend directly on factors such as quality of leads, frequency, consistency, mail piece, your phone skills, lead management, negotiation skills.......You see where I'm going with it.

The concern that begins to factor into the equation for me at this point has been the types and frequencies of crime.

I do attend the monthly GOREIA from time to time, but I do feel I should attend at a higher frequency than I do now.

A realtors study showed homes within half of a mile of a high-frequency public transportation were worth 41 percent more.There are a lot of factors to consider when evaluating the location of a potential investment, and a good real estate agent can help you identify opportunities that are most likely to payoff.

We buy houses at a frequency of 1 every 6 weeks.

Keep it simple, search the 203k contractor database, you will/should find one in your area, call a few then pick best one.I know your investor wants his own contractor, but his contractor may be simply more expensive because he will have to consider carrying cost for project as the payments  and frequency of payments are regulated by lender.

Regarding your question about frequency of mailers, every 4 weeks works for most of our clients.

Just look at the forum homepage to see the frequency with which posts are replied to or posted and you'll see that there is no lack of action happening.I realize you're interested in the numbers -- with a Marketplace post, that data is available.