My pocket invitations are costing me about $2.70 each (including $.85 in postage because they are very stiff), plus the cost of printer ink (no cost to me but most people have a cost for this). They are VERY DIY though. To order these pre-made on Etsy would easily be $7+/invite. You can save money by cutting your own pieces vs. ordering them pre-cut. I already had a great paper cutter (and have lots of experience in scrapbooking). Here’s a breakdown and some pictures.
All my paper products are from Cards & Pockets.
Postage: 85 cents
Envelope (Dark Gray): 21 cents
Pocketfold (Sparkling Merlot, the plain colors are cheaper): 80 cents
Belly Band (ordered 12×12 printed paper and cut it): 13 cents
Dark Gray Matting Paper for main part of invite: 23 cents
Patterned paper border at top and bottom (cut out of 8.5 x 11): 11 cents
White card stock (ordered from Amazon and printed on it myself): 9 cents
C&P Shipping cost per invite (divided by 135 invitations) 12 cents
Materials (glue, white pen, etc; divided by 135 invitations): 15 cents
Did my own design. Total cost = $2.70 per invitation. My total cost for 135 invites will be about $365 including postage.
I did skip envelope liners, even though I love them. Too much extra cost. I love invites but was trying to do highest impact at lowest cost. On the outer closure tile of the pocketfold, I printed the name of the guest invited (kind of like you would on an inner envelope). Used mail merge and it made that very easy.
I am also doing all online or phone RSVP, so that saved the expense of return postage (especially since you often have to hunt a lot of people down anyway) and envelope. You can make the RSVP a postcard (to get cheaper postage and no envelope) but make sure it is really heavy duty paper and it needs to be a certain size, which didn’t fit well with my design.
Keep in mind that postage rates are going up as well in late January. I’m sending my invites out right before that to beat the increase (very small increase but I like the single 85 cent stamps), but if I were doing mailed RSVP, I’d need to put the higher postage on them.