Are you using vinegar and water to clean your windows but finding it's just not doing the job? DYK commercial window cleaners leave a very fine wax coating on windows; vinegar and water alone will not remove this residue. The solution... just add a dab of liquid dish soap to your vinegar and water mix. After about 2 or 3 thorough cleanings, inside and out, you won't need to add the dab of dish detergent to your vinegar/water solution!
Window Cleaner Recipe: into a spray bottle add 500ml water, 125ml white distilled vinegar, 1/2 tsp liquid or powdered dish soap.