Every quotation will be different Mate, when you contact the Electricians you should expect an initial visit as to discuss what points /sockets, switches you require, how many etc, if the electrician is any good he will or should bring catalogs of types of accessories, Consumers Units for you to choose from, so there will be no confusion for both parties.
At this visit you should discuss with him the routing of any chases that may be required, along with what points you require, in places like the Kitchen, Living Room, Dinning Room etc any outside buildings, outside lighting that is to be included in the quotation, you will need to be clear, both you and the Electrician as to who will be filling in the chases, and to what point, ie finish ready for painting etc.
Asking people for sample quotes may be met with a no show from some guys, as they will not want to publicly show how they price for jobs.
You could after the initial visit, and quotation, post it on the Forum, omitting names and addresses of course, for opinions of what guys think of the quotes.
At least that's my take for what it's worth, remember to ask for recommendations from previous customers, also check if they belong to one of the CPS Schemes, (note, this last recommendation is not always a good indication, as there will be some bad boys around)
Oh and pay in stages so much up front, a percentage after 1st fix (wiring chasing, fitting boxes etc) (percentage after second fix and testing) keeping a small percentage back for snagging purposes.
Think of everything you want done to be included in the quotation, as day work for extras can become expensive. Keep detailed notes of what was discussed at the pre quotation visit, to avoid any contentious issues on completion, of each stage of the work.