Hello Dave,
Congratulations on your new home.
Presumably with the doors or windows still to be fitted, it hasn't been plastered internally? If so, it's ideal, you have a blank drawing board for modern networkification.
Before it is plastered up, run some cat6 behind steel channels [1] down the walls into each of the rooms where you want networking.
Feed those cable runs back to a central point where a (powered) gigE switch can be discreetly housed - under the stairs, perhaps?
Ethernet cabling costs very little so it's worth running more cable than necessary. That means extra cable runs to the region of the
idiot box, in readiness for new networked audio-visual appliances
In each room, terminate the cable drops into RJ45 faceplates next to existing wall sockets. The modular outlets look the tidiest. [2]
If the place isn't plastered / plasterboarded yet, this is a job for a competent DIY jobber.
The trickier bits to the job are perhaps cutting back box apertures into dry-walling or plasterboard, but that's presumably for the professional plasterer to do.
Also, getting the channelling to tack to (brittle) breeze blocks can sometimes be difficult. The plasterers get really miffed if they have to stop mid-job to refix channelling that's come loose. There's only 30 minutes working time with a gypsum plaster mix, so little time for messing around
It is easier (imvho) to sink some wall plugs into the breeze blocks and hold the channelling down using screws.
Doing it DIY, the whole house should be networked in a day and for under £100, unless you are moving here [3] then perhaps budget for a bit more
cheers, a
[1]
http://www.tlc-direct.co.uk/Products/SC1.html[2]
http://www.tlc-direct.co.uk/Main_Index/Computer_Accessories_Index/Data_Grid_Plates_KN_W/index.html[3]
http://www.dailymail.co.uk/news/article-2150981/Yours-2-5million-Jacobean-mansion-bath-100-000-year-maintenance-bill.html