We had ours fitted just before Christmas it was under a £1000, depends on the one you want ours was a Ideal with a 10 year warrantee, if you are in our area I could give you the plumbers Number.
Please try to avoid Ferroli as we had very bad experience, it broke down in the first 6 months and was always a hassle for 6 years till ve could afford another one. Now we have Vokera and are very happy.
We've just had a new Worcester boiler fitted, and new windows. The house is like toast now. OH would know how much he paid for boiler + fitting, but don't want to mention it in case he remembers I haven't paid my half.
~Baths~