Volvo Repair: Volvo S80 1999 turbo oil leak, s80 t6, volvo s80

Question
I have a 1999 s80 T6 and my mechanic tells me I have a small oil leak coming from the turbo.  What type of impact does this have on my cars functionability (if thats a word)? And is this something really expensive to fix?  

Answer
it  is not so expensive repair but  you are loosing engine oil and the oil leak will get bigger your turbo  produce lot of pressure and blowing  behind the turbo drain tube oil to outside you need to change the seals on both turbos .volvo delaer price of repair is $600 are you from chicago