just stick to a mobile number then they can get straight through to you.i dont understand why you need to have a landline,freephone etc as i dont want to be mithered off people in my leisure time!!
if they want a window cleaner theyll phone the mobile!! 
mine has a voicemail message that tells them exactly what i do for a living so if im not available they can leave a message.what could be simpler??
i have my address on my business cards so they know im not a "cowboy" if thats what some of you are thinking by only offering ONE number to ring me for a quote!!!
I agree with you by having just one number would be better, but the major problem with mobile numbers is they are used by cowboys all the time.
Every trading standards office in the land will say, never use a tradesman who only have one as a point of contact.
Yes you do get a lot of people who will take no notice and phone, but you also have a lot who will not call.
I first started off with my landline and moble number, I then dropped my landline number for reasons already given, I have now added my freephone number.
With the freephone number I get a report every month on the amount of calls I get, I have also noticed that I am getting more calls from the areas I now leaflet than I did before.
I also just used the freephone number, but I have found I get more calls if my mobile is also shown as well.