Orangey red hair - every time!

Hi,
Here's my long and probably boring story:
- for the past 10 years I've been having all over highlights (naturally mid brown), my most favorite color of which used Koleston 12/03 and 12%.  My hair is, as a result of many many highlights all over, totally blonde - not orangey, not strawberry, just nice, golden blonde.
- I moved to London recently.  1 salon couldn't go closer than 1 cm from the scalp (thus I arrived and left with roots), so I tried some DIY.  The lightest Nice n Easy, and another brand, for 2 months, both resulting in horribly orange roots.
- I went to another salon last week to try a correction - she applied very mild bleach (and maybe 12/01?), I left £100 poorer, and still as brassy.  With 1 cm of root, again.
- This week I decided to learn a bit about coloring.  I bought my own 12/03 and Welloxon 12%, plus Wella colour fresh toner in 0/6 silver.  I mixed around 15ml 12/03 with around 30ml developer (this didn't really seem like as much as I wanted- do the roots really need to be soaking wet for the whole hour, or do you just have to brush it over all of them?).  Left for 55 min, as per instructions.  I applied the silver stuff for around 5 min, at least.  Which I believe did nothing.
- I still have brassy roots.
- please don't tell me to go to a salon - I know they get a nice non-orange color but all but one hairdresser ever has managed to leave me without roots (shame I left him with blue hair), I have no money left, and I'm losing faith (one hairdresser last year tried to tell me that hair grows from the ends, not the roots).

I'd be so very grateful for advice.  What am I doing wrong?  Why can't I get past this orangey shade?  Thank you!

blue cancels out orangy tones in the hair. A blue based bleach, and then tone with your wella 12/1 do this at the root only.