Is this 2002 subaru impreza wrx worth it? $14,000?

I would say yes! But unfortunatley, a lot of WRX's and similar cars such as evo's vl commodores, and the like are thrashed beyond reason. You would have to worry about a damaged 'box, as is often the case with WRX impreza's. They have a notoriously fragile transmission. Jst check with the owner, and maybe get it serviced and have a professional check it out, make sure its all good.