Hi
We've recently bought our first house (which is more of a project! -
lots of work needed) and finances mean must DIY as much as possible.
We currently have an old back boiler system with hot and cold water
(plastic) tanks in a bedroom cupboard which we are thinking of
replacing (along with a hideous 70's gas fire attached to the back
boiler) I'm thinking of having a crack at some of this myself.
Obviously, being a plumbing novice, I will have a lot of research to
do before starting but any help on these basic questions would be much
appreciated:

1) Is this a realistic project for a DIYer or am I biting off more
than I can chew!

2) From a 'developers' point of view (as we hope to trade up quite
quickly) is it even worth replacing the system. The existing system
does work and the house is only a modest 2 bed terrace worth about 85k
when finished. Is the work likely to add more value than it costs?

3) I need to clarify what I can do myself by law. I was thinking I
would get a CORGI pro in to do all the gas fitting. Am I right in
thinking I'm ok to run any new non-gas pipe work and install / replace
new radiators my self plus physically fitting the boiler without
making the gas connections?

4) I have had a couple of people in already to quote but they can't
seem to agree on what needs doing - in particular if existing pipe
work to radiators is up to the job or needs replacing. Its standard
15mm copper and looks ok to my untrained eye (apart from a couple of
leeks round radiator valves which I intend to replace anyway) People
trying to make work for themselves? Could do with some guidance on
this.

5) Is there anything I can do myself regarding replacing the old gas
fire and removing the back boiler to keep costs down?

6) New gas pipe work will be required as any new boiler will be in a
different location and we want to install a gas cooker. Again, any
sort of preparation work I can do here to keep costs down?

7) We currently have an electric shower which has seen better days.
Any thoughts on if it is best to replace this like for like or
incorporate the new shower so that the new boiler supplies the hot
water to it?

8) What order to do things in? Better to have pro in first and then do
new radiators, pipe work etc or best to do all the diy stuff first and
then get pro in to finish off and get gas connections done?

9) Better to buy boiler myself or will Corgi guy get it cheaper?

10) Any website or book recommendations to help with this project?

All of the above assumes the new system will be a fairly basic Combi
system with water tanks being removed to make room for the new boiler.
I know there are a lot of opinions out there as to the pros and cons
to this type of system, but as far as I can tell it's the only real
option for someone on a very (very!) tight budget ..... unless someone
knows different.

Thanks to anyone who took the time to plough through that lot! I'm
sure its pretty boring old ground to the more experienced readers but
I don't want to be caught out by new regs reading old threads. Any
help will be Massively appreciated!