If you are having a custom clarinet made specifically for you then keep in mind you are paying a high price for that customization.
If you turn around and want to sell it expect a loss. Maybe a significant loss, or expect to hold on to it for a long time before a buyer comes along.
Why would anyone want to buy a "new" used clarinet from you when they could order a custom made clarinet and get what they want for the same price with an original buyers warranty ?
Here's some more info on clarinet value. It doesn't really answer your question but then we don't know what makde, model etc clarinet you are buying
http://clarinetperfection.com/ClarinetValue.htm
