Ow... I think my eyes just rolled into the back of my head.

But...

If you're fortunate to be located in a non-homerule state, then you're probably just going to stack your local taxes on top of the percentage for the state tax for sales made within the state in which you're located, which still doesn't provide any sort of a breakdown for reporting purposes... But at least it's manageable, because it keeps it simple.  This is because your taxes are determined by the tax rates at your location, and not the location you're shipping to... at least within your state, and therefore a single rate for your state inclusive of state + local taxes is both manageable and adequate, and Commerce can correctly collect this amount for the transactions within your state when it sees that destination for your customers shipping address.

However...

If you live in a "home rule" state, then there is currently no way to make Zoho Commerce compliant without the cost of an additional integration, as you need to use collect tax based on tax percentage that's been assigned to the address of the shipped destination, and that can vary widely across the state.  There is simply nothing in Commerce that supports this functionality.  So, I can certainly configure the 2.9% state tax rate for Colorado. Does that make me compliant?  Not at all.

Furthermore, these same rules may also be applicable for any business that sells over a certain dollar amount to any other state where they have a threshold dollar amount that exceeds a certain level (e.g. $100,000).  If so, you may have tax liability in those states as well, and also need to be configured to collect taxes for those locations in the same way.

I again reiterate that there is a ridiculously simple method that Zoho could implement into Commerce that can addresses this one issue for most ecommerce businesses to maintain reasonable compliance.  And while not perfect, it would be at least be adequate for most small businesses to demonsterate that they've taken practical measures to comply with all the relevent sales tax laws that apply to their home state.  The straight forward solution is to simply perform the tax rate lookup at the zipcode level instead of at the state level.  That's all.  It's so simple that my dog could code it while locked in a sausage factory (if he were provided the API, that is).  The following thread elaborates on this subject in further detail:

Now, to cover all bases.... Yes... There is another option... I can pony up $50 a month for Alavera + extras, which is the base price.  The cost can actually be much higher depending on a range of other factors.  This integration is said to include live tax lookup by the address.  But... why should I have to do that when the fix I've proposed is so simple to implement.  Why not simply make the extraordinarily simple changes that are being requested to allow a home-rule-state US businesses to maintain proper compliance without Alavera.  Just provide the option to permit tax lookups at the zipcode level.

-Bryan