If you didn't have your return address printed on your envelopes, what did you use? A stamp? A label? handwritten? print them yourself?
Also, for both the return address, and the address on the RSVPs, does it matter what name we put above the mailing address? FI and I are co-hosting with my parents. (Not sure if that matters or if I just put my name since I'm the one who will be collecting and tallying them)