What SaaS/Software do you use for infrequent invoices and tax tracking?

I recently completed a small freelance project (<$5K) and was about to send over an invoice but was wondering if there was some service you all recommend to track the tax burden for this project. I don't do a ton of freelance work (maybe 1-3 projects/yr) but would be willing to pay ~$100+/yr for the peace of mind when it comes to taxes/invoicing.