With regard to No. 1, yes, you are still eligible for the VAT refund from purchases in Paris and all other EU countries you visit. But you must process your all forms at customs when departing from the last EU country. Meaning that if you depart from Germany, you process all your forms at the airport there. UNLESS your return flight has a connection in another EU county before returning to the US. So if your return flight from Germany has a connection in Amsterdam you will likely be told by German customs that you need to process the forms during your connection in Amsterdam. The exception to this is if your purchases are going in your checked bag (not recommended for anything of value), in which case you should be able to process in Germany,. This is my experience, but I have heard of others who were able to process the forms at their departure airport despite having a connection within the EU, so it doesn’t hurt to try. But you should also make sure to allow for lots of time for any layover in a EU county before returning to the US.
With regard to No. 2, I am not familiar with the the net VAT refund amounts for the various EU countries, but my understanding is that the differences are negligible (usually about 1-2%). Hopefully someone else can shed some more light on that.
Have fun and happy shopping!
Thank you so much for your valuable info! I’ll be traveling around Europe but will fly out from Europe from CDG airport. So I’m assuming I would just do the VAT refund in Paris? Do I have to claim anything in another country (ie Belgium or Germany)?