WFP is quicker but higher running costs so turnover needs to be higher. So you could have 2 different window cleaners, 1 trad 1 wfp and although the WFP does more houses and higher turnover the trad guy could earn the same or more in terms of actual profit.
People will only pay a going rate for the area. Wether its wfp or trad makes no difference......
When buying work though you will probably loose some customers along the line if you are changing them from trad to wfp or vice-a-versa...
Rgards
Mr H