I set up a shop there about a month ago but haven't gotten a sale from it yet, I have however gotten sales from goodsmiths.com during that same amount of time, which is also free and you can export your etsy shop.
I have been using Square for a while now, both on my WiFi enabled iPad and on my android HTC Sensation and am very happy with it. You can use it seamlessly between the 2 devices when you need to. As a long time propay user I really enjoy the ease of Square, no paper receipts to deal with and the iPad app let's you easily track item sales even with cash. A keeper for sure.
I work at home depot and they most def have aluminum tape, it is in the aisle with the duct work. I'm not sure that it would work though, it is very thin, like aluminum foil. I found another website where another person had made these and used brass for the backing. I posted the link a few pages back.
I sell and ship mostly clothing items so I always ship priority. The boxes are free and the actual cost to ship priority vs. parcel post is never more than it would cost to purchase boxes/packaging to ship it in. Also, as a bonus, the USPS will deliver the boxes right to my home and pick them up for me.