How to best clean windows?

You won't keep the outside clean longer as every time it rains dirt from the house washes over them. I just use vinegar and water solution or buy a bottle of windshield washer fluid. That is made to clean road oils and grime from the elements. It is a lot cheaper than the blue bottled stuff like Windex. You can get a whole gallon for less than the price of one of the small bottles of regular window cleaner.

I don't think there is a way to keep them clean longer ... Maybe something like rain x , but I would worry it might cloud up after awhile . I use a mix of white vinegar and water and use a squeegee !!!!

Alcohol . I buy in big bottle and put in a sprayer

Deborah...Dirt just happens on windows especially through the different seasons and pollen is awful around here now. I just finished mine, inside and out, using Windex and newspaper. Many people like the blue shop towels that we can purchase at a grocery store called United Grocery Outlet. My husband likes them much better than newspaper and they really do a good job! I just always have the newspapers! Good luck....I will watch your question for other answers just in case someone knows a secret to keeping them clean longer!

Here's a post that might help https://chascrazycreations.com/eco-friendly-window-and-mirror-cleaning/

First, take an equal amount of vinegar and water and mix them together in a spray bottle. White distilled vinegar will work best for this. Then, spray the solution on your windows and let it sit for around two to three minutes. Lastly, use a gentle cloth to wipe away the cleaning solution and avoid any streaks.