How about making the sitting "absolutely free" with a minimum order of $250.00+? This will show the potential client that you are confident that they will love your work and be willing to pay generously for it. Remember that nothing ventured is nothing gained. The economy is dreadful at the moment and professional photographic services are among the most likely luxuries to skipped over in favor of things which are more practical. Let the quality of your work and free sitting fee be what sets you apart from the other studios in your area. Word will spread quickly. One caveat- this arrangement will require a "proof session" where you sit with them and choose which pictures will be printed. You will want to show them big beautiful images from which to make their selections- perhaps projected on a screen. You can make slides from medium format and larger negs for this purpose. Sending them an email with triscuit-sized jpgs. of the session aren't likely to generate much enthusiasm and could be misused without your permission. Think big! Sofa-sized prints on canvass are still popular in certain circles- Don't bother with the K-Mart crowd.