Flat dollar discount or percentage?

I'm wondering which is more likely to catch your eye? A flyer offering a flat $100 off or a coupon offering 10% off. We're looking forward to the "Sold on Springfield Township" event on September 20 as a way to market our building and remodeling services, and I'm preparing some marketing material. This event is an all-day house-hunting affair sponsored by Springfield Township. It starts with an overview of the community, and then folks will fan out to visit open houses throughout the township. There will be prizes and free food, and each participant receives a "goodie bag." Our Building Images flyer will be in the "goodie bag." Since the main focus of the event for Building Images will be our remodeling services, I'm planning to include the coupon. I'm picturing the recipient as either a homeowner who needs to fix-up a home to sell, or someone looking to buy an existing home that may need some renovations to fit their needs. Which would you prefer? $100 off or 10% off?