I never told ANYONE I was changing to WFP...if a carpet fitter or ceramic tiler turned up at my house to do a job, I would not question the tools he carried...if he had invested in tools that made his job easier and quicker, then good luck to him. The price of £200 he quoted is for fitting my carpet...how long he takes is his business...I just want a carpet in my room!!
Honestly, I have had no problems...I would make these suggestions...
NEVER offer to return to trad...this is the way it is being done and that is it...if they dump you, trust me, you will be laughing at them within a couple of months as you get WFP custom to replace them and they are struggling to get a trad cleaner who can be bothered to come into the area for 1 or 2 houses
NEVER mention spots...just trust the system, clean the windows and collect your money.
IF someone mentions spots on their windows, then explain about dirt build up in frame recesses and over the next clean or 2, they will be immaculate.
Remember the major advantage of being self employed...YOU are the boss and YOU decide how you work