Is there a way I can get a additional info from the customer once they have bought something from me?

[mnspro]

I want to be able to offer the customer the chance to supply additional detail to me after a sale. For example during checkout after they have committed to buy I want to question them for some information (if they agree to supply it) like an additional phone number for example. Is that possible?

I know there is the chance I think to add message to seller to provide additional info but I wanted to specifically question the customer, ask if they agree to something and then if they do for them to provide me with particular info that I then request of them.

The only solution I can think of is have the customer provide the info by adding a message to seller. Perhaps I could customise checkout?

Any idea's?

-Mnspro