my work is all within 3/4 miles of where I live but I include travelling into my hourly rate. That is not to say I charge the customer but at the end of a day...say 5 hours..I will have earnt 5 x my hourly rate.
WFP will be used by most in the future but no way could anyone transport the trolley and barrels of water required in anything other than a van or car.
The only way to be walking around with a cart is if you are just using ladder and trad tools and as curious says that was being done 30 years ago.
There is an old guy around here who does it and his charges are in the region of £3 a semi...he is out in the area at 7-8am and still trundling around at 5pm...
he cannot have many years left in him and his customer base must be huge...are those people in for a shock when he retires and they have to get someone else in to quote