I use this property and another one as my business line of credit. 

Also be aware of Unrelated Business Income Tax (or UBIT) on leveraged real estate inside of an IRA.Or better yet, since you are self-employed - go with a truly self-directed Solo 401k plan, which would be a much better option and will help you avoid the UBIT on this investment.

I invest in land and have done entitlement/zoning and other DD work successfully for years.A broker called me this morning on a property I have on a busy interesection and has a QSR client who likes the location, but does not want to do a ground lease, only a build to suit. 

A formal business built on this seems overkill as you’re essentially paying someone for a service that already has standard model.If you and the parnter have distinct business tasks/abilities (i.e. not what you would hire an agent or contractor for), such as off-market lead generation, that’s a different discussion.

Even if you create a non-CA LLC, if you are managing the business from California, you will likely be deemed to be "doing business" in California and therefore likely subject to CA taxes.

I think you can model a decent double digit return but how do you transition to actually pulling money out? 

Regarding finding discounted deals......That is the reason why I started a wholesaling business. 

The program has been great for my own STR investments and my co-hosting business.

To become a true business owner or investor, you need to leverage your time through others.

I second @Erik Estrada Chase offers great programs for business, multifamily, and conventional loans for commercial properties.