From NAR
You don’t have to be a tax expert to talk with sellers about the potential tax consequences of their sale. Understand the basics—including what constitutes a primary residence, what qualifies as an improvement and what documentation sellers are required to have. Then, be prepared with the names of tax professionals who can help them evaluate their individual situation, as well as links to credible tax guidance online. (The Internal Revenue Service is the authoritative free source of guidance. See “Topic no. 701, Sale of Your Home”.)
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