What is the best way to clean a vehicle on the inside windows?

Does it have an after-market window darkening film on it? If not, use the same product you are using on the outside of the window.

I use Windex all the time.... to see which side the streaks are on... wipe up and down on the inside and side to side on the outside or visa versa

Hot water and vinegar or household ammonia.

Norwex cleaning cloths work great and have leave no limgering odor. Windex and a soft rag also work well. Whatever you choose to use, make sure to clean the windows out of the sun to avoid streaking.

Try denatured alcohol on a clean cloth. Then wipe over again with a glass cloth. Glass cloths are kind of like microfiber cloths, just thinner and softer.