Anything < £600 is good.
Anything < £500 snap their hands off.
Make sure you get a fixed price deal...
When I had mine done about 18m ago they quoted me a price according to the labour time listed in autodata (or similar), IIRC about 6 hrs labour.
It took them >15hrs in the end. And thats in a garage with the correct tools and on a lift. Every single bolt was seized solid and/or rounded and needed to be cut out/welded to etc.
You are likely to get a better price at a good multi-marque garage rather than an Alfa indi IMO. Indies know what a pig they are!
I was very, very glad I didnt attempt myself and the garage, bless em, stuck to the quoted price. If I had been paying the labour pro-rata it would have been very expensive indeed.
-1998 916 Spider 2.0TS Lusso-
H&S Corse stage 1.
CATCAMs stage 1 cams with Savali custom ECU remap.
305mm discs with 166 4-pot callipers.
Ragazzon exhaust mid section.
Biscione Racing 2x70mm rear section.
17" Zender Siena wheels with 3mm rear spacers.
etc etc etc!