The role that debt plays in a exchange is probably one of the most misunderstood areas of 1031 law. Many people (including qualified intermediaries, CPAs, and attorneys) believe that you are required to have debt on your New Property in an amount equal to or greater than the debt that was paid off on your Old Property. This is NOT, In fact, a requirement for a 1031 exchange.
The actual requirement is two fold: you must buy equal or up, and you must reinvest all of the cash. Assume for example that you sell a purple duplex for $100,000 and you buy a replacement property for $90,000. You did not buy equal or up; in fact you bought down. As a result, the $10,000 buy-down is taxable—yes, the entire $10,000 is taxable, and you do not apportion any of the original cost of the duplex to this gain.
It Doesn’t End at 15%
Second Homes & 1031 Exchanges
The Wall Street Journal - REAL ESTATE FINANCE Joint Property Ownership Picks Up