I have done this many years now and my experience with it is excellent. Traverso players are very reliable!
I do not make any students model. I try to make each new traverso the best I can make.
However for students (and also for musicians) I have a special possibility to make paying easier.
I often make special payement agreements with students (and also with musicians) allowing them to pay over a longer period. There always has to be a reasonable payment when the instrument is delivered. Two pieces of information are made, a bill of sale specifying that the instrument is sold and how and when payements will be made signed by the buyer and the paper going with the flute signed by me specifying the initial payment. If this is done via internet there automatically is a registration of the way it will be done. Times can be relatively long. I make those agreements on an individual basis. I also do this with professional musicians because they usually are the RRR people (Routinely Really Rich).