Wilmslowwhite wrote:

I am looking at a small/cheap boiler - £300, with 4 rads and I reckon
the materials will cost £800 from a DIY chain.

I don't think you're going to find a (new) boiler that cheaply. For a
start, these days you have to fit a condensing model, which has caused a
step-shift in prices.

I will speak to a few plumbers, my ideal scenario would be for it to
work out cheaper alround for me to buy the materials and get a plumber
to fit for £500 cash.

You'll find that's not the plumbers' ideal scenario though! They
usually expect to supply and fit, which (a) lets them add a mark-up and
which your plan deprives them of, and (b) prevents the real issue of
what happens if/when it doesn't work properly - is it down to him (bad
installation) or you (bad equipment), whereas if he provided everything
there would be no question.

Can be done, though - have done it myself! ;-)

David