I think communication seems to be the issue here especially with your comment on how the PM is unresponsive.

One of the major issues I see is this.

Lot of the issue stems from pillars / blocks that sit on top of the soil in the crawl.

As to the quandary posed by the OP: The root of the issue is that it basically sucks to be an RE investor these days.

Even in towns where they desperately need affordable house if, they can’t get over the stigma of MHPs.The other issue you’ll run into is highest and best use.

@Nathan Harden- agree about OH ....I went to school at Miami U and lived in columbus area for a few yrs  ...many friends that still live there ......I live in Seattle proper ( near  Magnusson Park ...also  own  2  properties in Mason County ......father in law lives on  close to 10 acres close to downtwon Medina so we will be dealing with  figuring out the  best thing to do with this  as he gets  older ( he is  83 now) ...stay in touch

There's a good chance the issue(s) you face has already been discussed and answered.Ask questions in the appropriate forum.

Of course when doing the 1031 exchange your basis will carry forward into your replacement property.Where you have a potential issue is establishing your intent to hold those properties but immediately selling one or more them as soon as you have them ready. 

He was more expensive because now I gotta pay someone else to fix it.But here's the other side of the license issue.

And my #1 issue is I don't see any actions to address this in a meaningful, market specific manner.