I bought a decent set of rain gear about 8 years ago, for about $180 for the jacket and pants. I have worn them at least 100 days a year since (I use them as a winter top layer also) and they're still going fine.

I have fenders but I don't think they're as important as good rain gear.

I bought mine from Bicycle Clothing At Its Best--and Our Bicycle Clothing Is MADE IN OREGON! - waterproof breathable jacket and pants.

Looks like they've gone up a bit - $110 (on sale now) and $95. Worth it.