When a potential buyer calls, is there anything in particular that I should ask them before showing my home to them?
Sellers Answers

It’s always a good idea to get the buyer’s name and phone number in advance, so that you can confirm the appointment and follow up after the showing. Potential buyers tend to show up for the appointment more often when they know you have their phone number. Be sure to ask about their financing arrangements before you agree to show your home. Showing your home to financially unqualified buyers can be a major waste of time. 

Remember, there is a big difference between "pre-qualified" and "pre-approved" with regard to mortgage financing. One is a "looks good" statement, while the other is an actual commitment to fund a loan. Also, it is a good idea to verify their name and phone number in either the phone book or on the Internet, so that you can protect yourself and your valuables. Keep in mind that you are inviting strangers into your home and your safety is a key concern.