Making customer leave comments

[jtmace]

I want to force the customer to leave a comment when they are checking out. I need to force them to leave the year/make/model of automobile so I can verify what they buy will fit their car..

 

What is the best way to make sure the user leaves his or her comments. I was looking at javascript, but I need to be handled on the server side.

 

Any suggestions?

 

Cheers