Bear in mind that a micro brushless build will be quite tough if you don't have much electronics/soldering experience, a 250 is slightly easier just as the tolerances of everything are that much looser. These are the bits I've come to use after MANY iterations and failures... I am really fond of the ET 150 even though it's a larger rip of the RotorX Atom. I actually own an Atom frame and do plan on doing something with it by summer, there are some exciting micro motors coming out. Recently the Spadger has grown on me for ease of build and is what I am working on at the moment. These bits are all from Banggood, so free shipping. Sadly HobbyKing are untouchable on batteries, but that's all I order from them.
Frame:
Diatone ET 150 £13.38 /
Diatone Spadger 150 £12.07
Motors/ESCs:
Eachine 1104 motors + XM 10A ESCs + 2 sets of props £55.13
Flight Control:
Naze32 Acro £16.55
Battery
LiPo:
Rhino 610 3S £3.40 (HobbyKing)
FPV gear really is dependent on that you have already and your budget. I'm using the Quanum V2 goggles and a beat up RC305 receiver, the cheapest of the cheap but love them
Camera:
600TV Micro Cam £6.76
Camera Mount:
Diatone micro cam mount £1.58
VTX:
Eachine 200mw 32 channel VTX RP-SMA £8.07
RX:
FrSky D4R-II £18.23 but depends upon your TX of choice...
Some other useful bits to have...
Props:
4 pairs 3020 props £1.37
Better PDB:
Diatone V7 switching PDB 5v (Naze/RX) 12V (VTX) £3.44
TX Module:
FrSky DJT for 9x/TH9X/JR £20.69
TX Case (I use these for my TH9X and also for carrying 2 quads and lipos) £18.62
About all I can think of at the moment