Now that you have prospects worth going to the next step with, most will want to see and fly your plane. All things being equal, it is in the seller's interest to encourage the prospective buyer to come to wherever the plane is parked in order to look at it.
It is also best to agree on a price, lest the trip be wasted because you are too far apart on what you each feel the plane is worth. A phrase like "I'd hate to see you come all that way to look at the plane, if we might not be able to agree on a price" generally helps to get the process started or finished.  

Whatever you do, especially if it is a seller's market, don't fly the plane all over the place showing it to anyone who calls, even if they are willing to pay for the gas.
Even in a buyer's market, if the prospect is genuinely interested in your plane, he'll find a way to come to you. On the other hand, if the prospect is willing to send you a written offer and a deposit, subject to a demo flight at his location, and he'll pay for the fuel, then don't hesitate.

It goes without saying that the showing and demonstration flight is critical. The good news is that the buyer has already decided to buy your plane, so don't give him an excuse to say no. Make sure that it is clean and that all equipment is installed and working.
It is best for you to fly the plane from the left seat and let the buyer observe how well everything is working from the right seat even if the buyer is already qualified in your particular make and model and you are comfortable in the right seat, you still do the flying.

Click on any of the following to jump to information on completing the sale, from our "Buying Process" section: