They do not have any specific requirements, so it's up to me to come up with the statement format and frequency.

The gain on sale would go back to the IRA on a tax-sheltered basis, so long as the frequency of such transactions is limited. 

This is where I would start assuming I have a good CTR and a good amount of reach with a low Frequency. 1.

Now, there is a chance that a sellers preferred modality to perceive life is not VISUAL, rather AUDITORY, OR KINESTHETIC OR EVEN OLFACTORY/GUSTATORY, which in that case the seller may break away from rapport unconsciously because we are not in the way FREQUENCY.

Even Probate list would have a timeline different than an equity seller.The key is frequence of your message and also to mix in various types of direct mail pieces.Also remember that direct mail does not create motivation.

The two components that drive this are marketing; media, message, and frequency as well as determining the fail safe number.

"whole slew of variables" Wholesaling and marketing -depends on many aspects that @Jerry Puckett can answer, but FREQUENCY and BRANDING is important.

No Equity Deals (2006 - 2008 purchase) in Nice Neighborhoods - ListSource.com ---------------- Frequency - You need to mail 5 - 7 times over 3 - 6 months.

Each time that period is going to be about 2 weeks in a good scenario, but I could be wrong.Steps 1-5 will take likely 2 weeks alone if you are interviewing multiple agents.I don't know what the frequency is of deals falling out from offer being accepted until final inspection, (best I can find is a article stating nationally 3.9% of sales failed in 2016, up from 2.1% in 2015)  but it's a considerable pain for any seller to have to reboot that process trying to appease a single fickle buyer. 

So, charging higher rent and increasing the frequency of turnovers can actually net you LESS money than charging less.