The old self improver route of getting 700 hours etc. has now become the modular course. Ie. get PPL, hours build for 100 hours or so, do night rating followed by ME/CPL/IR which when totalling 200 hours with exams gets you a shiny fATPL.
Depending on training establishments, time, ability, weather etc. £25-£40,000
The other route is Integrated, basically full time course for 13 to 15 months. Anything from £60-£70,000.