I've done that trip three times already.

Euro traveling for fun in the US with intention of buying goods to bring back home.

Usually a small handbag 30-40l with wheels should be the best option to move fast in the city and the airports. Grab basic stuff, in the summer you don't need much. 4 tshirts, 3 trousers/jeans/short cargo pants. Roll everything for better size economy. I'd carry the laptop by hand just saves space and the hassle of removing it from the bag in TSA.

I'd hold on the shopping to the last day (depends on what you intend to do/buy). I usually rent a car then everything sits in the car until I leave and I've bought 500-1000$ of clothing and stuff like that in outlet centers around the states. Then buy a cheap disposable suitcase (20$ as someone suggested before) and use it to pack and send back to your home town . It'll be destroyed, so you might use it at home to store stuff or something but not for travel anymore.


Not sure in PHL what's a good outlet center but you can use lists like this to find them.