A customer of mine has a very complicated price list and I have avoided making it interactive so far. The users currently fill in a price list and email/post it to him.

I will explain what the options are:

1/ Full kit - everything included appart from some accesories.
2/ Small kits - e.g. Wheel kit or fixing kit etc.
3/ Pick what you want from the full list.

Things start to get complicated now as there are things like alternate power sources; for example twin instead of single motors. If you have the full kit and upgrade to twin motors you pay a premium for the extra motor BUT you will then also need two drive shafts rather than one and possibly an updated controler.

I suppose I could have a kit for single motors and a kit for twin motors but there are other options like smooth tyre or off road tyres and all of a sudden I need 6 price lists and there are more options and 4 different models!

Any ideas how to approch this? I can use php and Mysql but would it be better using another laungage. But this would mean a lot of "if" "else" options or would "switch" be better?

What we are trying to do is reduce the time to process the orders and talk to confused people who are not sure if the need a twin drive kit to go with a twin motor setup etc.

I suppose I need a flow chart type of order where the user picks the main items and they are offered options. Depending on the choice the order is updated with the other items that need to go with the option choice.