Rust in the rear arches??
And yours is a few years younger than mine....where is your rust?
I'm not sure whether to have a go at it myself, or pay the money and get a body shop to tidy it up. I've battled rust on several of my (and the missus') older cars over the years - mostly (in fact all!!) Fords, but anyone of the old SSc fraternity may remember me going on about some rust that appeared to my horror on the driver's side (I had assumed galvanised!) doors of my then silver 9-5 saloon. This was thanks to a crap bodyshop repair done on behalf of the lease company before they disposed of it, and something I hadn't noticed when I bought the car........
I can forgive my 9-3ss this time round, as it is far older already than my 9-5 was back then, and has 4 owners worth of life before me..... but I still have nightmares about sanding and wire brushing rust, getting the Kurust on, using filler, more sanding, getting the primer on, then trying to get a matching paint aerosol, then lacquer, then rubbing compound blah blah.....