Based on my search results, unfortunately I did not find any listings that specify the cost to fill a 4.5kg gas cylinder. However, here are a few relevant listings that may help: The Lpg Gas Cylinder 4.5KG for R818 is an empty cylinder that would need to be taken to a gas supplier to be filled. Once filled, it should provide you with cooking gas for your needs. The Gas Stove 4 Plate With Fittings Stock Pots & 5KG Cylinder for R1199 comes as a bundle with a filled 5kg cylinder, so could be a good option if you need a stove as well. I hope this gives you a starting point to then contact gas suppliers locally for refill prices. Please let me know if you need any other info from my limited search results.