@Jesse Dominguez-Castelan You should also explore one of the quickest options to this situation - reach out to the seller financing provider and see if he'll extend the balloon a few more years.I did this in the past when my 5 year balloon was about up, it was a simple email checking if he was happy with the arrangement and would extend an additional 3 years. 

In addition to that, here are a few pieces of advice that might help you on your journey:Wholesaling as a Launchpad: Wholesaling can be a great way to generate capital and gain valuable experience in the market without the need for significant upfront investment.

Additionally, investing in real estate education through courses and seminars will help sharpen your skills.

(I had additional carrying costs from a HELOC, which meant I walked with around $45,000).Aquisition:We found this deal on a wholesalers website who we keep an eye on.

Additionally, my wife and I currently own a home in Encinitas, CA, that we purchased for $795k in 2016 and is now worth about $1.5M.

Add a pull out couch for additional sleeping.

A few additional items to help you: 1) If you have a Roth IRA, a Roth IRA can't be rolled into the Solo 401(k), only pre-tax funds.

Besides land, infrastructure/site work, and the building construction itself, am I missing any other major category of costs?

I dont really follow any other type of SM so i have to assume there are other sites that folks post on as well when they are upset with their investment and or who ever is running it.

@Cody M.I would add a Phase I Environmental Site Assessment as a contingency to any offers on properties more susceptible to environmental issues (dry cleaners, gas stations, auto repair garages, etc.)