Avoiding tax on a lot sale

I own a lot worth around $400,000. My mortgage is $175,000. I want to buy another property and would like to avoid selling this lot if possible because it is appreciating and the loan is 4.75% fixed. An in-law who has far too much cash sitting in CDs and money market accounts expressed an interest in becoming half owner of my lot and can pay me $200,000 in cash. The way I see it, if he pays me cash for 50% fractional ownership I will be getting the same amount of cash as if I sell it. Question. Is there a way to structure this deal so there will be no tax due and so I can keep the present mortgage?