Tires look great! Is it lifted at all or is that stock height?

I would suggest doing the cam and crank seals. My 98's were extremely brittle when I did my timing belt 2 yrs ago. (185k miles on them) They cracked as soon as I touched them.

Also they should replace the idler and tensioner pulleys. I also replaced the hydraulic tensioner for extra insurance, but that's another $100..

If changing the timing belt on a SOHC 3.5 is 'easy'...I'd hate to see hard! By the time I got done doing it myself, $800 sounded like a steal. I personally would be hesitant to trust Firestone with this job, but hope it works out for you!