eBtax setup with rules or exception

I have a problem with the rules application in AR and AP.  We have an multi org environment, two companies and differents exceptions to apply.

Examples:

1.  Company 1: 7% tax for all the transactions AP and AR (via interface), but in AP the manual invoice for basic suppliers (water company, light company, etc.) not need to calculate tax and for other suppliers.  I have to use the Products- Tax Exceptions or the Parties.  I read documentation but it is confused.

2.  Company 2:  0% (non tax), tax default, but some suppliers or categories need to calculate 7% and 5%.

If you have some similar like this?

REgards,