Maybe I'm reading this wrong but if you are to RECEIVE 4 snakes it is up to what the shipper feels is safe. Meaning if he or her chooses to use a larger box for the safety of the animals that is his choice. Now if you are willing to waive live arrival guarentee I'm sure he may ship them how you want as opposed to what is right. (I wouldn't though)
As for shipping rates, I personally usually charge a flat $50 or include it in the price of the animal.
Problems do happen with shipping and it does not make sense to cut corners there. Here is a link to a nightmare I went through in Nov. http://heathersherpsblog.blogspot.co...1_archive.html Scroll down to Nov. 18th. If this animal was not packaged properly it would have never made it. While you're there enjoy the site, it is a lovely one by a stand up person.