Basic equipment is all you need
The same high-quality window washing tools the pros use are readily available at home centers and full-service hardware stores. The whole setup is inexpensive and will last many years. In addition to a 10- or 12-in. squeegee you'll need a scrubber, a bucket (a 5-gallon plastic bucket will work), hand dishwashing liquid and a few lint-free rags or small towels.
Keep your squeegee fitted with a sharp, new rubber blade. Purchase two or three to have on hand. The pros we talked to change their squeegee blades as often as once a day. That's because you just can't do a good job if the edge of the blade becomes nicked, sliced or rounded over with use. If your squeegee leaves streaks or just isn't performing like new, don't hesitate to replace the blade. You can get a little more mileage out of blades that aren't nicked or sliced by simply reversing them to expose a fresh edge. When you store the squeegee, make sure nothing touches the blade.