If you want the highest rent you have to promote your place to as many people as possible. 

I assume a cash offer and a quick sale would further entice him to sell it, but what would the smarter route be for a bigger return on investment?

Many insurance salespeople will jump to promote this idea but it is your money, do your research and don't be mislead! 

At that projection it does make holding onto it slightly more enticing.

Lots of folks like to promote such self-partnering because it creates business for them.  

One, is interruption marketing; direct mail, phone calls, text messaging, blast email, etc.The other is letting the sellers come to you; build a great website, promote it through SEO, SEM, social media, etc.

Using an algorithm like pricelabs is clearly the solution BUT Airbnb just introduced promotions.

And then compounding with differing laws state-to-state along with a tenancy of many posters who are not investors but wannabe profiteers looking for free advice or outright promoters who are fraudsters, the category is ripe for problems.This is NOT where the successful probate people hang out.

This will either entice the renters in that will see the property as a fit, or not waste time with those that it won't work for. 

These are popular options if you want an ad and promotion free experience for yourself and tenants, but are less frequently used by single property landlords.There are a number of low-cost, or even free, platforms available that are able to offer you a lower price by advertising to you and your tenants and/or passing along fees to tenants (payment processing fees, applications, tenant screening, etc).