and I will follow you round and take all your jobs. LOL
It's all well and good what people say about charging more on this site, but sadly, the customer is the one that chooses the contractor and there is always someone willing to do a cheaper job. yourself for instance, you just said you would increase your charges accordingly.
If we all had a fixed price structure, say 50p for ground, £1 for 1st £2 for 2nd etc everything would be rosy price wise, and there would be no competition, but thats what business is about, not just making money but winning contracts, because you are better/cheaper than the competition.
Best bet, charge what you're happy with. If you feel you have been rewarded well at £10 per hour good, if you feel your work is worth £25 per hour go for it but work will be a little harder to get and keep, £50-£100 per hour (regularly) like some of these dreamers on here and I don't think you would have much work,
Oh and yes I would charge more for a 3 story and do. Keep your eyes on the competition and never think that the customer can't do without YOU.
Good luck
Steve a