Lexi_Pee Hi! to echo Mr. Donadillo above, it depends on circumstances surrounding the property (and the transaction).
generally sellers may engage the services of licensed real estate professionals (salespersons, brokers) to market and sell their properties properly. by doing so, you delegate most of the work. listing brokers (those representing sellers) ought to conduct due diligence on the property including assessing the physical condition, location, and of course status as to ownership and other rightful claims. (as an aside you can consider brokers as lead organizers coordinating with other professionals like architects, engineers, designers, and of course lawyers, among others)
after choosing a broker, sellers must authorize the former in writing (through an ATS or Authority to Sell) to market, find a buyer, and negotiate on their behalf. note though that the ultimate decision to whether or not sell to a particular buyer depends on the seller.
upon closing, you may opt to hire a lawyer for contract preparation and review if you prefer.
however in all successful transactions, lawyers are required for the notarization of sale documents (deed).
hope this helps! good luck! in case you need referrals for brokers and lawyers (or law firms) let me know!