Single Condo Unit-House Hack

[Gene Finley]

So I'm still very new to the forums and BP but I've got an interesting scenario to run by you all.  To set a bit of context I bought a condo in the West Loop of Chicago 2 years ago.  If you are familiar with the area it was a great buy.  I had to move and found a tenant via referral from my neighbor.  My neighbor has since put his unit up for sale.  I'd like to get creative and make him an offer with little to no money of my own to buy his unit and put my current renters in the his unit.  Any thoughts on the best way to accomplish this?