Each person who lost their property will need to rebuild their home.

(Get an owner occupant loan.)Can you seller finance it for more?

The gentleman Chris Koerner seemed well educated on the topic (mobile home park investing) and he gave enough information and follow-up documents that you could take the information and run.

Do all your due diligence upfront (see if you can get an inspection done before submitting an offer)On the lending side a DSCR loan is an option.

Do 80/90% of land 100% of construction loans exist?

The lots are owned free and clear so the loan would only be for the construction.

It's now been 7 years since our fire and cookie-cutter neighborhoods are about 90% rebuilt, custom home neighborhoods are about 75% rebuilt, and luxury homes about 50% rebuilt. 

You can gauge this risk by checking state average homeowners insurance rates.Few people live in cities that meet all the above requirements.

Quote from @Nicholas Dillon: I read somewhere that you can request to have your mortgage insurance dropped once your Loan to Value reaches 80%.

Most loans are sold to those two entities.