Radiators cost ~USD $160, expansion tanks ~35. Labor for DIY 1 12 pack of Labatts. Time= how long does it take to finish off a 12 pack, Eh?
Really, it isn't that bad. You should find a write up @ E38.org if you haven't looked there yet. But if you want to pay someone....I'm just guessing but I think I have heard ~4-500 USD at the high end.
When you reach 100+k if it isn't broken yet. FIX IT! The most mileage I have heard was 85k miles before it popped. Lowest 35k miles. Mine was done before I bought it at 40k miles. Avg. seems to be in the range of 55
9-04 Mt. Hamilton
2000 740i Impala brown