Would I need to modify my sale or purchase contracts when carrying out a 1031 exchange? When listing the property, does my realtor need to make mention that is a 1031 exchange?

No; the IRS does not require that the sale or purchase contracts be modified when carrying out an exchange. However, you will need to inform your realtor of the exchange and include a passage in the contract to inform the buyer or seller (depending on upleg or downleg) that you are conducting a 1031 exchange.

You may find the following example helpful for writing your own passage in the contract; however, you should consult with your Certified exchange specialist before including your own cooperation clause:

“Buyer {or Seller} is aware that Seller {or Buyer} intends to conduct an IRC 1031 exchange at no cost.