I had my dealer order the suppressor and I had to pay for it then. When the suppressor is shipped to him, he and I fill out Form 4, which he mails it, along with a copy of my trust, and a check for $200, to the ATF.
When the form is approved, it is sent back to the dealer who will notify me and turn the suppressor over to me along with the Form 4 and the affixed tax stamp.
I'm not sure how things go if you plan to manufacture a suppressor, but if you buy one you should be able to do a revised "Schedule A" yourself, adding the suppressor to it, then when the suppressor comes in, you'll give the dealer a copy of the trust, the revised schedule A indicating the suppressor, and a check to ATF for $200. He'll take it all and send it in with the Form 4, and all that's left is the long wait.
If you feel more comfortable by running the schedule A revision by your lawyer to verify, by all means have a chat with him/her.
"As an American, I was not so shocked that Obama was given the Nobel Peace Prize without any accomplishments to his name, but that America gave him the White House based on the same credentials"...Newt Gingrich
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