I went to my machanic on the off chance and he said "you haven't bought a car from that b****". It turns out he is very well known.
Like RDD he said that warning light is a potential problem.
He also seemed to the think the steam could be a HG like I suspected.
Anyway he has told me to get a MK4 Fiesta with 1.25 Zetec engine and take it to him during the test drive and he will check it over for me.
I am £100 down but also feel relieved as alarm bells have been ringing all day. Lesson learnt today if a car is at a garage still treat it like a private sale.
I feel annoyed at loosing £100 but also pleased I haven't lost more.
Thanks everybody here, I feel I owe you all a pint

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