How do I have access calcuate costs?

[Guest]

I am making a sale invoce, kinda like a reciept for my customers and I want
access to calcuate the total for me when I am done and also calcuate the
sales tax with the total cost. How do I set this up?

 

[Rick B]

Pretty hard to answer that without know a lot about your structure.

I'd advise you to take a look at the sample database, Northwind, that ships
with Access and see how they handle the invoice and the calculations there.