Before buying a house with a friend, perform your due diligence to understand their finances and any potential challenges (such as debt or poor credit). Also, talk through the various aspects of homeownership to ensure you're both on the same page. If you move ahead, "I highly recommend contacting a lawyer to create legal documents that establish financial ownership and responsibilities to the house," Boonzaayer said. "There can even be agreements on how to sell the house if there is a divergence from the plan."