It's always scary making a huge purchase. If you are nervous because the seller's agent is also your agent, then ask the agent if you can find someone else to represent you. Depending on your state laws, dual agency can only take place if all parties agree. As for a cash offer, you don't have to worry about the house appraising for much less and the bank not giving you the money for it. My advice would be to make an offer contingent upon appraisal, if you think it's listed too high, and then ask the seller's to drop the price to the appraised value. If it appraises for more, then offer them a fair or full price offer.