Is this a good deal/good set-up $50?

sounds like the deal is for items that are stolen. Seller sounds like they want to get the items sold quick. Amp looks pretty old and warn.. Sub pics are not great but who knows if there is anything wrong with it. You would also need to buy wires for everything if you don't already have them along with a box, since you can't play the sub without a box. Sub or amp may be blown also so its risky.. Probably better to save up and buy better products that you know will work and that come with a warrenty through the companie.