Just a few years ago, I remember purchasing other brands of "gas treatment" for 2 or 3 bottles for $1 from automotive supplies stores which advertised in Sunday papers. I am making a soda can alcohol stove and looked up the price of the Heet used as fuel and it is an eye popping $11 for 12 Oz at Sears.
There are other sources that indicate that Heet is $3 for a 12 Oz bottle and I checked at the Home Depot and it was $8 for a quart.
I was a working in chemical factories in my early career and know how dirt cheap methanol is. There must be some law against such blatant extortion by retailers. This behavior has started after 9/11 in the US and grown like a plague. E.g., Ice cream was 64 Oz for all of last century and now the new half gallon is 48 Oz. Same for orange juice. The new gallon of bleach is now 96 Oz. not the 128 it was for ever in past. If you write to the retailers you get a sugar dripping reply about market research and constantly adjusting to the products to the needs of people, etc.
I wish there was a simple design for a DIY stove that can burn gasoline.