Doors and roofs are the most common and easiest places to find it, but
check wheelarches and sills too.
Not exact matches
Check for corrosion underneath and around the
wheelarches, and make sure there's no knock from the main bearings due to running low on oil.
The SLR's signature scissor doors that swing out and up on massive hydraulic struts — a kick every time — give easy access to a cabin space that
checks in somewhere between cosy and cramped and buts right up against the rear
wheelarches.
No serious structural corrosion issues as such, but some cars suffer superficial corrosion, and the first place to
check is around the
wheelarches.
The worst section is likely to be the outrigger at the back of the front
wheelarch, where there's a mud trap, but
check all the other tubes behind the sills and across the chassis for pinholes or worse.
Don't be surprised to find rust, particularly around the sills and rear
wheelarches, but do
check that it's only superficial — the inner sills are a potential problem.