No. Before the meeting, make sure the prospective adopter knows that you don’t plan on completing the adoption on the spot. This takes the pressure off of both of you, and helps you bring the meeting to an end gracefully. Also, if you decide during the meeting that you don’t want to adopt your pet to this person, it’s often more comfortable for you to relay that to them via email or phone, rather than right there on the spot.
At the end of the meeting, suggest you and the adopter both take the day to think about it, and make a plan to talk the following day.