Moving kitchen/knocking down walls in victorian terrace - what is approx cost?

[MsHap]

We live in a Victorian terrace house - usual layout - through reception and then narrower room at the end (so L shape).

Kitchen is currently in the front reception room. (we didn't put it there, we've inherited this!).

Room in the back is in fact 3 rooms - the end appears to be a later addition (with flat room). Kitchen did used to be in the back room so I presume there are pipes etc there.

The works I am thinking of are:

1. knocking the back room into one big room and putting glass doors into the garden. Assuming that there are supporting walls - room is about about 8.5ft wide I think?
2. Moving the kitchen to either the back room (and having a long galley kitchen with dining table at end (room is about 13ft long).
3. moving kitchen to the back 2 of the 2 reception rooms - where there are no fittings.

For various reasons we don't want to extend into the side return.

We have no idea what this will cost - DH thinks tens of thousands, but I don't! I do intend to get some builders round but just wondered if anyone has any experience of such works.

Thanks!

No experience of what you are planning to do but from my own research / planned extension here are some completely random numbers to get you started:

building warrant fees and potential professionals drawing costs - £500 to £1k
Structural surveyors calculations - £250
New external doors - patio doors maybe £500 / bi-fold posh ones maybe £3k
New kitchen (units only) say £5k plus fitting, tiling, new appliances, electrics, plumbing and gas so another £2 - 3k depending on spec and access to existing drains.
New flooring throughout plus fitting £2k, again depending on what you go for
Plastering (walls and ceilings) and paint - maybe £1 - 2k if you paint yourselves
New doors and skirting - £500 to £1k
New radiators - another £250
Also new light fittings and switches, socket covers and extractor fan (cheap to buy yourselves from Screwfix or equivalent) plus new sink and taps.
The cost of moving services / pipework will be cheaper if you have a suspended wooden floor (likely).
Your best bet it to get a couple of quotes as I've not included actual demolition / build costs or costs of skips / waste disposal.
Also factor in the cost of vacuum bags / potential new hoover and/or hire of industrial vacuum cleaner for all the dust (tip from PigletJohn).

It's all the little auxiliary things that add up!!
How competent are you at DIY? What would you be willing / able to do yourselves to save money if necessary?

thanks for this - we're extremely incompetent at DIY, but are going to do decorating ourselves in the rest of the house. Anything beyond that is too difficult- we lack skill and talent! (and time).

Do you know how much knocking down walls/putting up supporting beams costs?

Afraid not. That's what you need a local builder to quote for as it will depend on where in the country you are and the specific ins/outs of what you are planning to do.

The other stuff is easier to quantify as, for example, you know you have x metres of flooring and your preferred laminate is £y per sqm plus fitting; you need 12 (say) kitchen units and that'll be £3k plus fitting; you can roughly cost up new appliances and your preferred worktop etc etc