I&#039m having problems with queries in MS Access. What I have been trying to do is have a dropdown list that has the price change as the user selects different items. For example, when they select PIII 900 instead of the standard PIII 600, it will show PIII 900, add $600.<BR> All I want to do is update component prices everyday in the database and have the website update itself. I have created a cost field, product id, product description, serial #, product value, markup, etc for the table. Then I have a product query which calculates selling price for each item by multiplying cost by markup and adding cost. Then I created another query for the standard motherboard, another for standard RAM, etc. I did this so that I could pinpoint the costs for each standard item seperately. Then I will probably have to have seperate tables for each category, such as one for RAM, one for CPU, etc.<BR> Anyways, back to the problem,--I am trying to get the add/subtract values, so in the product query I put in a add/subtract field to get the price differences to upgrade or downgrade CPU&#039s, I select the CPU standard table selling price to get the default CPU selling price and subtract the selling price field in the selling price table. I expected to get a positive or negative value, but instead it has a popup that says insert value. What am I doing wrong? Does it have to do with relationships or something like that. You can email me at kprag01@yahoo.com. Ohh, by the way, I&#039m looking for someone to help me in my business, Prag Computer. I need help developing the database, and other areas. I can either pay you give you ownership interest in my company. Let me know if you are interested.