I'm part time and I've done the first 18 months trad and I'm glad I did so I've now got the speed and skills. However I'm shortly going van mount wfp. January is a bit dodgy to go full time on ladders if the floor is damp like it usually is that time of year. I'd say go wfp sooner rather than later. For the time being you'll need a few scrims, sill cloths, ladder prob 3.5m long (ladders online are exellent) squeegee (I used to use 14" but now I use 12" and hardly do any detailing) t bar for mopping windows, rectangle bucket glass scraper. Best thing you can do is go work with a trad window cleaner for a couple of hours to learn the ropes. I did and it sped me up no end saved well over an hour a day.