As an investor buying rental properties, the buyer should never have to pay a fee to purchase something. 

There is a "sponsor exemption" but that only allows an unlicensed person to raise money but it cannot be more than 50% of their duties and the pay they receive cannot be based on how much they raised.If you have never raised $, a family office will be off the table as they typically want the company to ahve atleast $50-$100M in assets. 

Could I change your mind if I told you that 80% of people who work with mentors achieve their goals?

Personally, I prefer to target tenants with full vouchers, as they won’t have to pay anything out of pocket. 

Also keep in mind, terms other than price will play a role in getting you offer accepted too.

We are General Contractors and part of why my cost for the conversion is so low is because we have the resources to pay at cost and the property is located in a county with lower labor costs than other parts of California.

Regulation will say you have to be registered and pay hotel occupancy taxes, but your unit may not qualify for registration. 

Could always get lucky and sell to an investor who pays higher, or it appreciates faster as it becomes more desirable with density increases.

How would the bank even know the gross pay amount?

I'm wondering if you are having difficulties with tenants paying their rent.