We have a converted BBQ roaster that we used to roast green coffee beans four pounds at a time with excellent results. It uses propane and comes with two propane tanks. Actually the roasting drum is rated for eight pounds, but we liked it best with four pounds of coffee beans. The roaster is for sale for $400. With the roaster comes our home made cooler to cool the hot roasted beans. Buying all the equipment new (BBQ, SKDrum kit, cooler, propane tanks), would add up to well over $1500 Canadian.