Twice a year...
Mine all come apart and tip inside the house so other than patio door, there's no outside work. 50's ranch homes - ahh! Double hung sashes and storm/screen windows, there are 4 panes (8 sides) and a screen per window. Wash & dry each screen and vacuum and wipe the sills then add the doors and it takes the better part of the day. A lot of work for sure, but clean, sparkling windows are so gratifying.
I use Dawn dish washing liquid and microfiber washcloths, dried with flour sack towels. Always a load of wash on window washing day.