Part of the reason I decided to invest in rental real estate wad that I wanted to be able to pick an investment for purely financial reasons and leave the emotional and social influences out of it.

I focus most of my marketing on my sphere of influence, current and past clients.  

For me some other factors that can influence my amount is how much I want the house and how much it costs.

For me a big factor influencing my decision on who does my contract work is how well they communicate.

I've seen people come and go over the last 15 years.From speaking with you at The Influencer and the Ram, sounds like you were also looking at tax liens.

I want to spend my time purchasing and renting properties, not pampering or influencing HOA board members.As Steven Covey noted, work inside your circle of control or influence.

Are there other factors that influence these decisions?

As an agent, working your sphere of influence is going to be critical.

Your 'sphere of influence' or whatever needs to know you are looking to help a seller unload their home burden.  

Way too many variables  to let the tax assessor influence my opinion of value.