How do you manage sales tax calculations for physical and digital goods?

I am looking at my options for calculating and filing/remitting sales tax. We have nexus in about 15 states (40-60 filings per year since most states require quarterly filings) and we sell both physical and digital goods, which complicates things as some states exempt digital goods completely, while others exempt them from taxes but include them in nexus calculations.

I am looking for any tips, tricks, hacks, etc., for how you do sales taxes. Do you fork over $5k+ for a TaxJar plan? Avalara? I actually just talked to TaxJar and it seems like unless you’re on their professional plan ($9k/year + $30 per filing ? ), their nexus calculation won’t exempt digital products (waiting for confirmation on this).

Does anyone have a cool spreadsheet, public app, private app, etc., that they’ve been using? A sales tax person? Curious to hear what others are doing and bonus points if you have the same physical vs digital sales problem.

I am also running into a surprising lack of objective information on sales tax management software. We are trying to open an international POD store. Have talked to Avalara, and was not impressed. Very expensive and far from transparent. Very low scores on support across all credible review platforms. Sales tax management is mission critical, and the lack of objective information is frankly very concerning.

Does anybody have experience with any sales tax automation software? One would think this would be a hot topic.