Stop hanging out with your deadbeat buddies that spend all day drinking, talking sports, and otherwise wasting away.

Getting a local realtor to give you and ARV would the best bet but you can use sites such as Redfin (be careful of Zillow's Zestimate) to get you in the ballpark. 

I bet there are options available to you such as using a "buy before you sell" (orchard, homelight, homeward, etc.) bridge-loan type program, or you may be able to use a HELOC or other bridge financing.

Hey @Chance CovanIf you're exploring options beyond traditional financing and haven't owned a primary residence for at least 12 months, starting with a bridge loan might be your best bet.

I don't know what the ten year appreciation rate will be, but I'm betting it will be insulated against any negative macro trends and positioned to outperform other markets, over the long term. 

I'm not a lawyer but I bet he could sue you if you don't let him move in and have a case.

I'd bet you'd be better off getting separate loans from the same lender when it's all said and done.

Your best bet is if you continue with the new build partner up with a reputable builder and learn.

If you are at the stage of your life that it makes sense house hacking is your best bet. 

Trying to go no HOA would be your best bet if you really wanted to puruse this strategy.