Please help me structure this deal.

[Steve Maginnis]

Greetings.  This is not an investment deal, but it will require some creativity, and I hope some of you have some experience in structuring similar deals.  My wife and I own a small lakefront property that has been used during summer months for the last three years.  We have decided to take advantage of the crazy market and have our primary residence under contract to close in three weeks.  Our plan was to live at the lake house until we can find a suitable property for our "final home" once the market stabilizes or "corrects".  

A friend turned us on to someone who has two lots they want to sell off market, on our current street.  Just under an acre combined with 250' of water front.  Existing pier permit, ramp and 3BR septic.  However, the owner says she only wants to sell one, half acre lot because they want to build or place a mobile home later on, when they downsize.  We really want/need the entire lot to have enough room for everything we desire. 

We would like to offer her our current lake house in exchange for the double lot.  The value is very similar.  The creative part is, we will need to stay here after we do an exchange, until we can build our home, which may take up to or more than a year.  The obvious answer is for us to do a sale/lease back where we stay and rent the home until the build is complete.  I really don't want to have to pay rent though... The seller is not in a hurry to do anything soon, and will not be interested in occupying the property for a while.  I wanted to see if anyone has any other creative ideas of how we can put this together?  Maybe add her to our deed, with a contract to remove us automatically at a certain future date?  Or we can do a land lease for her lot?  .  Neither of us owe anything on either property at this time.  

I think once we can begin building, it will only take about 3-4 months. Problem is, everything is so expensive here, so I was hoping to wait about a year in hopes of pricing coming down.  Any help is appreciated.