You are offering less than market value and then selling that contract at a higher value.

Or, if that doesn't happen, the first one of you to sell a house will have the proceeds of that sale yanked from you by the court before you even touch them, even if it's ten years later. 

I've had clients pick up a half dozen homes without ever putting more than 5% or 10% down or selling any of them.

You can get higher but the rates will be higher as well and it will be a lender that doesn't sell the loan to Fannie. 

Or should I sell and jump start my real estate acquisitions?

I'm a part of partnership that attempted to do a flip in Fl, but due to market conditions, bad contractors and multiple change orders, etc....looks like we'll be selling at a loss. 

Signing it knowingly and selling their short sale property to a family member is Mortgage Fraud.

My personal opinion is that unless there is no other way to sell the house, subject to should only be used when BOTH parties are sophisticated investors.  

Just remember if you sell it, make it your primary again by living in it for 2 years, or buy a new property using a 1031 to avoid capital gains.

I've also avoided paying Capital Gains Tax on selling my crypto.