Ace, to be honest, that was over 35 years ago. Rules may have changed, I don't know. I talked to agents in the local tax offices (feds and state) and they laid out the process based on what I told them I wanted to do/charge/etc. I wasn't well established yet in my actual business and didn't even have an accountant then. The agents in both offices took down my info, checked with others in their offices, and got back to me a week or so later if I remember correctly. I do remember both came back with the same answer.
No biggie, It's not like there's a fortune in it anyway ...
Now, the way I see it, it's too much hassle and expense to bother checking into it. If you want, you can chalk it up to a side effect of regulation limiting the market by increasing costs, rather than limiting through direct taxation. Tax advisors cost money. I'm no longer willing to bother.