I read thorugh the relevant NYS Law about Sole Prop. LLCs, and did that filing myself.

I have a CPA who prepares all the annual forms -- I handle the sales tax remittance quarterly filings myself.

He gives me, every year, a collection of estimated filings for the upcoming quarters.

Oh, yeah. Sales tax authority... You want that. Maybe your banker/credit union can hook you up with a credit card merchant account for 10 bucks/month + usage or something. THAT comes in handy occasionally ( Yeah, we take Amex... )