The Mandarin one needs general fettling and has a leaking brake doseur valve, the Cobalt one needs a head gasket and other work.
The mandarin one has been left standing for three years, the Cobalt one for seven years.






The cobalt one during a block test for HG leakage. Note the colour of the dye has changed to green from blue...and all those bubbles....

I've washed them both to get the moss off and had a look under the Cobalt one today and it's in really good shape.
One thing I looked for was that all four jacking points are straight with no rust on the body at all and only a very small patch underneath where the underseal is flaked off.
The Mandarin one isn't as pretty, but other than the leaking doseur valve and completely seized wipers and sunroof seems like a go-er.
The Cobalt one also had seized roof, height selection control (which I've now broken) and wipers, but the wipers were easier to free off. I had to lever the mechanism with a crowbar with the wipers on and lubricated on the Mandarin one. All done now though.
The neighbours think I've flipped..!!