If you are looking for a solution to this problem contact RefocusX on the Partner Solutions Directory.
RefocusX is the Lead HubSpot Partner for Chargebee “Quote to Cash”. This integration is currently on the HubSpot Marketplace and will automatically calculate sales tax on HubSpot quotes. It will also issue Digital Payment Links with the correctly calculated sales tax direct as a HubSpot workflow email.
It can calculate the correct sales tax in multiple countries and is fully integrated with the HubSpot Sales Hub and Deals Module
Finally Digital Payments are live on HubSpot!!!