Not sure I agree with this Luke. Lots of people like to pay with cash still, particularly older folk. Makes you look unaccommodating to refuse it.
I agree, especially with smaller jobs.. I would say to the OP I charge an hourly rate, doing quotes is a pain, I do it for some customers but it takes too much time, after a while though you will especially not not massive jobs get to know roughly how much the materials will be (Although I still always seem to underestimate how stupidly expensive materials are). So I tend to just say there and then, I would estimate parts will be about X, plus I think it will probably take me about X amount of time @ X pounds per hour, obviously if I find unexpected things then it might take longer but I explain to them that I find thats the fairest way, I only charge for hours I am onsite, I dont lark around, I find its just the fairest way to charge.. I'm not the cheapest, not the most expensive but I would say I probably get around 90% of the work...
Being prompt, if you can give them a price there and then not mess around you often find they might go oooh thats more than I thought then you can explain normally the thing that catches people out is cost of materials, they just dont realise how expensive materials are, gone are the day where the majourity of the cost was in labour, now it seems like the majourity is in materials.. Be friendly, reliable, give them a date you can do it, make it the easy option for them... I am also a landlord and so deal with trades, you know what the worst thing I find is having people say "Ok yeah ill try and drop in at some point ill give you a ring", I dont know if im going to hear from them again so I try other people, if you say "Yeah no problem are you about this evening ill pop round take a quick look for you, work out what is needed and give you a rough price".. People come off the phone and its like a relief that its sorted and they don't phone other people, you then are more likely to get the work..
You will always get some cheap
bottoms.. think my last rejection which was a while ago was replace two consumer units in a flat (on peak and off peak), from old rewireable fuses after it failed landlord EICR (That I didnt do).. I came in at a reasonable price, not overly cheap but it wasnt the nicest of jobs, customers response... "Nah I can't afford it, its ok I wont bother, ive met the regulations as I have had an EICR done", I tried to educate her that because it failed she needed it done but she assured me she was correct...
Have you thought about doing any charity work if you have spare time, I have a job to fit a defibrulator for a charity, I am doing it at cost price (Materials plus a little bit to cover my expenses like insurance etc), my company name gets put on the defibrulator and there is going to be an opening with some press releases etc with my company name, puts you out there in the local community..