Avalara - Avalara AvaTax connects to the software and delivers sales tax decisions based on precise geo-location in more than 12,000 taxing jurisdictions in the U.S.
As of now we will be keeping the Magento Default Tax method activated.
Apart from these if the client comes up with any specific requirement, we shall be able to that will be catered specifically for that project.
Taxes will be applied on shipping or not will be configurable from admin panel.
Tax can be configured on customer and product level for different states in US: