Operating costs of indoor blimps

Inspired by Scylla’s nightmare experience.

I must have one!

Anybody have one of these, or something similar? How often do you have to refill the bag? I think taking it out to a store would be inconvenient. What would a little refillable tank and regulator cost?

It’s currently on the Zany Brainy site…operating cost is $15.00 plus about $6.00 shipping.

http://www.zanybrainy.com/global/store/product_detail.cfm?TID=12623946214269910304027963&Site=Toys&rs_section=keywordsearch&GroupID=6597&GroupTP=Model
It looks like you can buy disposable tanks of helium (intended for inflating party balloons) for about $42.00. That would probably inflate the blimp many times.