I recently bought a particular pick-up roller assembly from Trainz on the Bay. It was $6.60 and shipping was $4.74. It was send in a small package. I didn't have any shipping charges complaints.
However, due to shipping charges I sometimes buy more items than I might need to save on possible future shipping charges. Or, I might actually buy another item to average down on shipping charges. I just bought the Menard's REA boxcar, but I added the REA van on a flat due to combined shipping.
Alan