By the way...get your Paypal set up (if you don't have it already) and also find a local box company. You'll need many boxes of the right size. I would suggest buying boxes for 1-2 models (10 x 10 x 8) and also boxes for 3, 4, 5 kits (about 16 x 10 x 8). There are box manufacturers in most cities, so you should be able to get them local...but they are not that expensive even online (use google and find a company at least your state...to keep shipping cost down).
You'll also need shipping peanuts and bubble wrap...which you should also buy bulk. Peanuts come in huge bags (as tall as you) and bubble comes in huge rolls (about 3' diameter). Google for local company if possible. one company usually distributes both.
If you are able, buy boxes 100 ata time...you will need MANY!
Paypal allows you to ship VIA USPS or UPS, and you can print the label from there also. Shipping will be the biggest part of the job. It takes some time. Your payments will come in at different times, so its hard to set one day for shipping.
Over all...you will enjoy the selling experience, but only if you have the time.
Like everyone has said...try a few out on this message board auction, and post here again once you have them listed!