Nobody can comment on what's equitable without knowing each partner's strengths & weaknesses and the specifics of the property being purchased but here's what I picked up on immediately: Why not form an LLC and have a partnership agreement? 

ThanksSuper market dependent and property specific.

If we can help with any General Contracting specific questions please let us know.

What specifically did you do differently on this property transaction, than an owner-occupied property transaction?

Penalties:Misdemeanor of the first degree: This can result in a maximum imprisonment of one year and a fine of up to $1,000.Civil penalties: You may also face additional civil penalties depending on the specific circumstances.Permitting issues: Local permitting authorities might withhold final approval, revoke the permit, or pursue other actions against you, maybe not give you the CO. 

Where are you getting stuck at specifically?

I have a cash buyer looking specifically in Richardson.  

@Aaron Landauhappy to help, but you said you don't want the 'standard advice'... so what specifically are you looking for?

Most cities have specifics like this for STR properties.

Get to know the specific neighborhood, RE is hyper-local, there is no single market in any metro area, it is comprised of many micro-markets.