Local Sales Tax Mod (with admin!) for testing

[LadyHLG]

THIS DISCUSSION HAS BEEN RESUMED WITH A NEWER VERSION HERE:
http://www.zen-cart.com/forum/showthread.php?t=111782



I have been working on a new sales tax mod with built in admin interface for Zen 1.3.7

This is the first mod I have ever done so I am posting here to get some feed back for anyone brave enough to try it out. It has only been tested with an unmodified version of Zen 1.3.7, so I can make no assumptions on how it will behave with a modified version of the cart.

This mod does not overwrite any files and creates one new table for the database.

It allows for taxing based on zip code, city, or suburb(for those using the suburb field for counties) and could be expanded to tax based on other fields as well.
It is specifically designed to compound taxes to whatever zone taxes you already have set up. Which means you can apply multiple taxes to any zone based on different criteria.

One example of how to use this mod would be -
Set up a statewide sales tax for CA of 7% using the standard zencart zones method.
With the Local tax mod set up a .75% tax to apply to 94203 zip code
You could even add additional .5% sales tax to be applied to just the city of Sacramento.

So if someone in the state of CA purchases something for say $35.99
They would automatically be charged the 7% state wide tax of $2.52
If they lived in the 94203 zip code they would also be charged an additional $.27
AND if they lived in the City of Sacramento they would be charged an additional $.18

Finally, the mod uses the "Basis of Product Tax" option in the Admin -> My Store to determine whether to use the billing or shipping address to base the local tax on.

I hope others out there may find this useful.

LadyHLG