"People buy when they are ready to buy,
not when you are ready to sell."
Follow-up! Follow-up! Follow-up!
Send them a thank you card for meeting with you. Send them your monthly newsletter. Send them an article you clipped from the newspaper, or found on the internet, with a personal note from you.
The sale may be next month or next season or next year, or in 17-months, so stay with it.