I just learned a helpful tidbit from an Avalara support agent.
When testing Avatax, either in their Admin console or in Sage, and you don't have a street address, as long as you have a City, State, and Zipcode, you can enter "General Delivery" in Address Line 1 to validate the address.
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Bob Pfahnl
General Manager - Silicon Valley Office
DSD Business Systems
CA
408-641-0922
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