I got a 5 gal drum of kerosene for like $15.... It will probably last me 10 yrsI asked one of our company aircraft engineers (Qantas) and was told that you can usually substitute kero, Jet A1, and diesel with products like WD40, CRC and RP7. The main effective difference is that the spray products have a “carrier†that reduces viscosity, which may allow faster penetration and make things a little quicker. He points out that kero is a dam sight cheaper.