Just rang my dealer and they want £270+VAT to set it.

Rang another local dealer and they want £80+VAT to check plus the cost of labour for adjustment.

Am I being robbed?

Should only cost you about £50-60. (including adjustment).

Check out www.alignmycar.co.uk for your nearest Hunter equipped garage  ON THE WAY: BMW F21 M140i
MERCEDES GL350 - Metallic Navy Blue w/Grey interior

GOING: BMW F31 335D MSport+ xDrive Touring
GONE: Land Rover Discovery 4 HSE - Stornaway Grey w/Black Interior (wish we'd kept it )
GONE: BMW F10 520D MSport - Carbon Black
GONE:MY12 RRS SDV6 HSE Sumatra/Ivory/Grand Black Privacy glass

Had mine at a local Indy LR garage, cost £120. Don't they need some fancy gizmo to adjust it on the RRS ?? Thats why i thought Joe Bloggs Motors can't do it - I may be wrong  FF 4.4 V8 Soooo looking forward to this bad boy
Ex 2006 RRS SC - garbage
Ex 2016 135i M Sport - dream car
Ex 2003 RS6 Avant - piece of cr*p
Ex 2014 320d X Drive, M Sport Touring - ok I guess
Ex 2007 RRS TDV8 - bloody loved it
EX 2007 FL2 XS - not so bad

There's been talk on here of putting the car in 'tight tolerance mode' presumably via diagnostics, but I had mine done without it and the car drove as straight as an arrow, unlike the crabbing it came out of the factory with  ON THE WAY: BMW F21 M140i
MERCEDES GL350 - Metallic Navy Blue w/Grey interior

GOING: BMW F31 335D MSport+ xDrive Touring
GONE: Land Rover Discovery 4 HSE - Stornaway Grey w/Black Interior (wish we'd kept it )
GONE: BMW F10 520D MSport - Carbon Black
GONE:MY12 RRS SDV6 HSE Sumatra/Ivory/Grand Black Privacy glass

Is it true it's best to put new tyres on to get the most accurate alignment?

i just had mine done after new bottom arms at a local independent tyre place, hunter wheel alignment and they said £60+vat but because it didnt need much adjustment the charged me £40 cash with a before and after printout and i watched him do it.

I am pretty sure that you should have a full tank of fuel when getting your wheels aligned, I can't remember where I saw it. 2006 RRS SC Bonatti Grey (the 55th car/van I have owned)
2005 GSX 1400 K5

LR's procedure is with full tank or equivalent weight added. 2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed