There’s a rigid plastic type material that’s used in dairies and on farms that I’ve seen used.

Legal Implications & Ramifications : As an example; the iconic PCH homes in Malibu and many in the upper foothills might not permitted to build back, certainly not to the same extent or materials.

The problem is you can't afford to properly make repairs when you are dealing with the lower tier properties and go with the cheapest bids doing nothing but putting duct tape on issues that will become recurring or believing you are making the repairs correctly but use inferior labor and materials because its all the property can absorb cost wise.  

Overseeing tradesmen while they work on your properties sounds like material participation to me.

If you are not rolling over to a custodian, but just changing the plan administrator and recordkeeper, you should be able to retain the titling of the investments, which may simplify the process. 3) You should be able to retain the current bank account for the Solo 401(k), but may need to switch to a banking partner that is more compatibly with the Solo 401(k) platform you use. 4) If you have a self-directed brokerage account tied to the Solo 401(k), you may need to make some adjustments there. 

Does anyone have experience with Ivory Home’s predesigned materials packages?

I've gathered more knowledge than I can implement with all the BP content and other materials, lol.

There's some excellent relevant & recent material from very high quality individuals on this forum.

Price out as much as you can in terms of materials and estimates.

However, for building materials, we get 99% of them from the four mentioned!