The hatch-back (Wagonback per SAAB) is a very good design. You can fit a full-size washer in the back.

I used to drive 99's, which is the precursor to the 900 and shares a lot of parts. I could change the clutch in mine is less than one hour. The transmission remains bolted to the engine, but the radiator must be removed. I didn't have A/C though, and having that would increase the time required for the job.

I don't know if this is still the case, but parts for the 20+ year-old 99 were easily available at SAAB dealers, and were not as expensive as you might think.