Here's a little hint that may help. I don't "wet" the envelopes to seal them. I use standard double window envelopes and seal them with a glue stick on the flap. The self stick envelopes are pretty good but in my opinion not worth the difference in cost.
I used to do it that way but with the decline of dot matrix printers the cost of the imprint type forms skyrocketed. And I'd think that you'd have to pay a premium price for a dot matrix printer nowdays that would print through multiple copies.
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