Do used Mazda cars have rust problems?

Yes based off of others reviews, Mazda's do seem to rust quickly compared to other cars. But you can take preventative measures by getting your Mazda sprayed with anti rust before, during and after winter to protect it. Personally, I recently bought a 2008 Mazda3 sport gx at 250km (phew I know), but the previous owner meticulously had the car sprayed for the winters and kept the body well maintained, and now there is virtually no rust. Myself, the used dealership and my mechanic neighbour were shocked because Mazda's are KNOWN for their rusting issues. I recommend just spray the body 3x a year, take care of it and if you notice rust appearing or the typical bubbling, go to your mechanic asap... Usually if caught fast it can be worked with. Good luck and zoom zoom!