It's normally 40 to fill that's out here in wantaugh at a welding place. But city could be less or more go on google type in welder in your area I'm sure something will pop up then call before u head out.
note that all tanks have an expiration date and will eventually need re-certification which costs about $40 for a 10lb tank. if you can get one at a local place that will take trade-ins at refill, that is best (IMO).
I fill mine for $22 for a 10lb tank in lower westchester (yonkers)