Second-Best Household Disinfectant

Obtain Chlorhexidine Gluconate Solution, 2% from a veterinary supply.

A gallon will cost between $12 and $25, depending on where you buy it from.

Obtain a clear plastic 1-gallon bottle (the water-clear ones sold with drinking water inside are excellent). Put one ounce of the Chlorhexidine Gluconate solution into the gallon jug, and top up with water. You will end up with a rather attractive pale blue solution.

The resulting solution is a strong disinfectant (but not as broad-spectrum as The Best) that is safe on nearly any surface. It is also moderately persistent, and its effectiveness is not affected by organic matter. It is also very inexpensive, because that gallon jug of Chlorhexidine Gluconate Solution, 2% is going to make 128 gallons of disinfectant. Even if you pay $25 for the concentrate, your disinfectant will cost less than 20¢ a gallon.

There is also a Chlorhexidine Scrub available -- this is the same active ingredient combined with a compatible detergent. This is not a good general purpose disinfectant (because of the detergent) but is an excellent cleansing product. It is substantially more expensive than the Solution.