Does exhaust will be rusted at some point?
 

Currently, I am looking for an exhaust for the car. does all the exhaust that exist these days will be rusted after couple of years?

That really depends on the material it's made of.

I see you're located in Portland, Oregon. In Portland you will not have much problem with rust, yes it rains and is wet BUT they do not use salt on the roads in winter. Look at any North East car if you want to see rust, many cars in the NE are rusted underneath when purchased new.

Factory exhaust will rust if not washed after a salty winter drive. Someday I will own a house with a nice garage and build a lift and water hose inside my garage to be rust free.

The only exhaust that will not rust will be Titanium or pure gold(if they make them). Everything else will eventually rust one day, some just do it faster than others.

Salt/winters will rust almost anything. My factory exhaust already looks 3 years old.

So, another question. For the exhaust with titanium tip or burnt tip (that blue-ish ending) those color will came off if it got rust?

The color shouldn't come off of a titanium tip if the color is burned in. If it's anything like what Greddy did with the Spectrum Elite exhaust on the GR STI (they painted the tips blue to mimic burnt titanium tips), then when you polish the tips, it will come off.

My factory exhaust has 2k miles on it and has surface rust already.

Stainless steel is a great alternative, titanium is pretty pricey. Any of the 300 series stainless steels should with stand road grime. Under car washes are still well worth the money.

questions of Stainless steel...SUS304 or SUS305 better???

my factory exhaust has a drop of rust im in middle north of NY state i put a SS cat back on and it still shines i have 5400 miles on the car. nothing underneath other than the exhaust system from the cat back had rust on it.

I just put my summer wheels/tires back on my car and got a look at my factory exhaust. I couldn't believe how rusted it was after just 1 winter.