The all-purpose cleaner that works on countertops, glass, and appliances is embarrassingly simple: mix equal parts white vinegar and water in a spray bottle, then add 10 drops of tea tree essential oil. The vinegar cuts grease and dissolves mineral deposits, the tea tree oil provides antimicrobial action, and the total cost per bottle is roughly 15 cents. It works on every surface except natural stone, where the acid in vinegar can etch the finish over time.

For scrubbing power — sinks, tubs, ovens — make a paste of baking soda and liquid castile soap. Sprinkle baking soda on the surface, squirt a thin line of castile soap over it, and scrub with a damp sponge. The mild abrasive action of the baking soda handles stuck-on grime without scratching, and the castile soap lifts oils and soap scum. Rinse clean and the surface gleams without any chemical residue or fumes.

The third essential is a floor cleaner that works on tile, laminate, and sealed hardwood. Add a quarter cup of white vinegar and a tablespoon of castile soap to a gallon of warm water. Mop as usual. Skip the vinegar for unsealed wood floors and double the castile soap instead. This formula dries streak-free and leaves no sticky residue that attracts dirt, which is the main problem with most commercial floor cleaners.

Store your DIY cleaners in clearly labeled spray bottles — dark glass if you have included essential oils, as light degrades them over time. A full set of three cleaners costs less than a single bottle of brand-name spray and contains zero synthetic fragrances, dyes, or preservatives. Your cleaning supply shelf just went from a chemistry experiment to three simple bottles.