I see alot of affordable manufactured homes (with land) for 55+ but is this a good age group for section 8 in the area?

Yes ,rent it to someone with 2 or 3 young boys around the age of 3 to 5 years old .  

At some point (either over time/age, or location) you have to make a decision to include a PM as another tool in your toolbox toward growing a profitable portfolio, and gaining your time back.

At that 6 to 10 year age of a house, things start to go wrong. a/c goes out, faucets start leaking, carpet gets worn out.If you are going to rent, dont do a rehab on the property.

As you stated, appraisers are looking at square footage, age of roof, HVAC and water heater, electrical, foundation, windows, doors, year built, location.

I can't imagine living with fleas in this day and age. 

Maybe the margins on your rentals aren’t great in his eyes, maybe with your real estate success taxes are going to be an issue, maybe he’s anti debt accumulation, maybe hes unaware that some markets didn’t react like CA during the last recession, maybe you are heavily weighted towards real estate and he’s just trying to get you diversified more.

As a past software developer, website developer I found TIN oddly lacking in obvious data fields:  beds, baths, age.  

Whenever a state or a muni is willing to give away massive tax breaks to attract big, anti-union businesses, and in turn ask the citizens to pay little state income tax, it's clearly a "pro-growth" environment.

Now days, being the internet age, there are several websites that sell you there programs for finding, flipping, and selling properties. some provide you will everything you need to do it all right from your livinroom and they even have a list of investors willing to buy your property right from the web as well or possibly after a personal inspection .