@OP You mentioned you're planning to use Proseries. I'm pretty sure that's the one that my “neighbor accountant” used, and I helped him convert to Drake, which is what I'd used when I was in taxes, cause his costs for Proseries were ridiculous. Per-return fees, additional fees for efile, additional fees for each state return, etc. etc., I don't remember exactly what the fees were but something along those lines, and they were nickling and diming him to death. So, make sure you've reviewed the fee structure very thoroughly. In my tax prep days (which granted wasn't for long), I used Drake, and liked it pretty well (though it's the only one I've used, besides Turbotax for personal). Been a little while since I checked the prices, but it was something like $300 for the base system which included 15 returns (counted by social of primary taxpayer, so Mr. Smith with Federal and 10 states still just counted as 1 return), then $15 for each additional return, or unlimited for $1500. If you started out per-return, everything you paid counted towards the unlimited, so after 95 returns (15 initial + 80 per-return), you'd convert for free to unlimited. No additional fees for anything. Though, they did add a cloud storage system that could be bought, but wasn't at all necessary if you had secure storage of your own.
I'm sure the prices are a little different now, but probably still following the same basic structure.
EDIT: Just looked up Proseries, and either it's not what he'd used, or they've changed their pricing structure to appear less gouging, cause it looks now like they offer a truly unlimited. They also have per-return and some other options; maybe he'd just selected a package that didn't suit his business? Or maybe he used someone else? Or maybe their pricing structure changed? Either way, I still liked Drake and their pricing structure, but looks like Proseries might not be the one that he was paying ridiculous amounts for.
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