from my advice rural properties and developments aren't successful and you are climbing an uphill battle. sounds a little niche. we focus on developing and not reinventing the wheel. if this is truly what you want to focus all your time and energy on then visit the closest 5-10 of these that look like the ones you are interested and ask if they'd expand or build a secondary one. do a lot of research before you just take action 

If it’s the latter, then you’re going to need to devote an immense amount of time and energy to becoming a full time agent.

The roof, AC, plumbing, electrical and flooring will eventually need replacements.

A 7.0 releases some 32 times the amount of energy as the atomic bomb used on Hiroshima. https://www.omnicalculator.com/other/earthquakeI am fully aware and well versed. 

I am considering purchasing empty lots priced roughly $10-15K below market value.My plan is to offer owner financing for the land.These lots have water, drainage, and electric connections available, and mobile homes are permitted.The area is experiencing significant development, with the lots surrounded by new single-family homes.I would really appreciate any advice, feedback, or suggestions.Thank you

-Structural (foundation, wall, ceiling and floor)-Roof and Exterior(Roof Condition,Gutters and Downspouts, Siding, Windows and Doors)-Plumbing (Water Pressure,Leaks, Drainage, Pipes)-Electrical (Wiring,Outlets and Switches,Breaker Panel, Lighting Fixtures)-HVAC(Air Ducts, heating and cooling)-Water and Moisture Issues(Attic, Mold and Mildew)-Kitchen and Appliances-Bathrooms-Pest and Insect Problems-Safety Features

We had to do a lot of electrical work, bathroom, kitchen rehab, total paint and a new roof.

Electrical next but mostly for eligibility purposes. 

-flips and BRRRRs are very time consuming, energy intensive, and hands-on. 

Then it's simple, build the home, find crews to do the work (you should already have them basically from the prior step), excavation, concrete, sealing, framing, roof/gutters/siding, windows, insulation drywall, plumbing, HVAC, electrical, finishes, etc. basically in that order.