Theres a big list of things which they recommend checking on the R-Tech Website before taking your car to them.
On my 6R I did the following....
Full Engine Service Genuine Parts
Millers 5W40 Oil. Is this the correct oil for my car?
NGK BKR7EIX Iridium Spark Plugs
New R8 Coil Packs. Aren't these a kind of luxury item?
New Revo Intake. Forge twintake already on.
New PCV Rev R. Is this necessary if mine seems ok?
New Diverter Valve Rev G and then fitted a GFB DV+. Got a new rev g but not the gfb+.
New Cam Follower. Already done.
DSG Oil Service & Filter change. Is this a diy job?
Haldex Oil Service & Filter change. Does this apply to my 06 gti?
Strict diet of Shell V-Power.
Thanks for the replies guys, I can do certain jobs myself but can't get underneath to do the oil and I take it the dsg oil and filter are under there as well?
I've already done the cam follower and the dv will be replaced when I have my exhaust modified and my springs fitted, as I said the pcv seems to be fine but I need to know the answers to my questions to bone lorry so I can get the right bits and not waste money on stuff not needed 
Sorry about the delay, Been busy driving Trains around
I will try and answer your questions...
1. Millers 5W40 Oil. Is this the correct oil for my car?5W30 is what VW Recommend, However this is quite thin when upto temp and on a tuned application has been known to burn. VAG Quantum 5W40 or if you can stretch to it Millers NanonDrive 5W40 is a better option.
2. New R8 Coil Packs. Aren't these a kind of luxury item?They are no different to the OEM Black Coil packs other than the Colour, However if your car is still on the original items then they are most likely to cause you issues when you have had the car mapped! This puts more strain on your Ignition system and so the Coil-Packs can begin to fail causing a Miss-Fire. A set of Genuine R8 Items are available for under £100 so for piece of mind I replaced mine and they look better than the Black ones
3. New Revo Intake. Forge twintake already on.Not a fan of the Forge Intake personally but it will be fine for the job.
4. New PCV Rev R. Is this necessary if mine seems ok?Mine was also fine but again if you car is on the original then I would replace it, The latest Revision R has a much better One-Way Valve fitted. Again piece of mind and for what it costs to replace it can save a potential loss of boost pressure if your original fails.
5. New Diverter Valve Rev G and then fitted a GFB DV+. Got a new rev g but not the gfb+.A Stock Rev-G will be upto the job but bear in mind that it will still fail, The Rev G is the best OEM Diaphragm version available but many people are encountering them splitting especially on tuned car. The GFB-DV+ is a fit and forget item which also improves throttle response too.
6. New Cam Follower. Already done.Excellent.
7, DSG Oil Service & Filter change. Is this a diy job?Is your car DSG or Manual? If it has a DSG Gearbox then yes I believe it can be done yourself, There are a few threads on the forum floating about with a DIY guide on doing the DSG Oil & Filter Service. I paid an Independent to do mine though, Much rather someone do it that has done many before.
8. Haldex Oil Service & Filter change. Does this apply to my 06 gti?No, Your car is Front Wheel Drive.
