I agree with the previous two posters. Your budget is just right for getting a quality bicycle, and that trek would be a perfect bike to get started on. I say purchase the bike shop rather then the bike - meaning buy a bike from the shop you feel most comfortable with- it makes a big difference.
If there is a Bike coop in your area, they would be happy to accept your donation.
I did some very quick research and it seems like there is NOT a bike coop in your area. As the other two posters indicated goodwill is the place to go.
I agree with the previous two posters. Your budget is just right for getting a quality bicycle, and that trek would be a perfect bike to get started on. I say purchase the bike shop rather then the bike - meaning buy a bike from the shop you feel most comfortable with- it makes a big difference.