agree the door knocking can be soul destroying but its part of the apprenticeship,only the strongest survive. in the early days id no idea what i was doing and it used to get me down and then i found a teenage girl who went pumping out my leaflets in the evenings. this built my round up. although it felt a bit like i was cheating by not doorknocking ,it worked. i paid her a tenner per hour and sometimes she struck lucky and i had no end of windows to clean the following day. she also told anybody who would listen "he charges £8 usually" and that REALLY rakes em in to call,you can then up the price a tad once you arrive with ladder on the shoulder
its a numbers game,you might need to leaflet/door knock a 100 doors before you get a strike, but you WILL GET LUCKY in the end .
having said all that,if you are high priced you are onto a loser(my opinion). its worth finding out what the big trad firm in your town charges (if you are trad) ,then come in a quid or 2 less than them and you will pick up the cast-offs from that firm . if you can handle these cast-off pickey bugger types you will get a toe hold and later can cast them off yourself when you pick up better types by being seen on the street