Really shoddy treatment and business practices. Definitely do the BBB complaint. Also regardless of the time involved take it to small claims. They might move faster and get you on the docket in a timely fashion. Next get together with some fellow winter visitors and make up some pickets and picket the place and discourage people from stopping there. Stay off their property and don't tie up traffic. Check with the Chamber of Commerce and see if they are a member and lodge a complaint with them. Write a letter to the editor of all the news papers in the area. Take out a classified ad in the want ads telling how they ripped you off. Be sure it is all true and verifiable. Make an inquiry with the local fire department regarding whether or not they pass their yearly safety checks. Are their employees doing the dispensing of flammable gas trained in the proper procedure. Do they have the proper number of fire extinguishers and have they all been inspected by certified fire equipment maintenance personnel. Turn up the heat on'em. They'll be glad to return your 100 gal. tank and probably full too.