I just had my timing belt changed on my 99 Prelude and I paid about $550 at my local Honda dealership. I believe that Honda doesn't "recommend" a timing belt change until you go over 100,000 miles, so at 80,000 I wouldn't worry about it, especially if you're planning on selling the car soon. I had about 90,000 miles on my car and decided to get it done because I do plan on keeping the car for a couple more years.