The type of business engagement and the level of interest in the counterparty or its assets influence the goals of a due diligence inquiry.For instance, a cordial agreement between a potential buyer and an experienced seller could provide the groundwork for a long-term alliance, whereas a hostile asset sale during bankruptcy would call for a different strategy.

For your question you posed, two factors would influence my decision: 1) my opportunity costs - in other words what other options do I have at the time, and 2) My stage of life - at points in my life I have been willing to take a bit more risk, and have had bandwidth to take on that risk, and others I am not so willing to take the risk and do not have the bandwidth. 

I had ZERO influence on it getting stolen.

I agree that the sphere of influence created by going through the degree process and meeting all sorts of folks related to it could be huge for opening doors that may or may not be missed without it.

I do out of state investing but I studied the market over 6 months and spoke to several agents, contractors, Sphere of Influence before jumped in.

What key factors should influence my decision on whether to sell now, offer seller financing, or keep the property as a long-term rental?

This is a nuanced topic with several factors that can influence the outcome.

Their pricing decision will be influenced by all kinds of crazy things and in this market, is higher than what you can pay as an investor.

I will find out this week if there are any further complications beyond the "mixed use" appearance even though there is no longer commercial influence on this property. 

But imagine the network and influence of its members.