Quite unfortunately, the automatic gearbox of our P-reg Punto Selecta seems
to have given up.  The car is otherwise in good condition, and the engine
starts, but the car won't drive forwards or backwards.  Whether we engage
Drive or Reverse or Low, it's just as if we had engaged Neutral.

When the car breakdown actually occurred, it had made a loud noise, such as
of heavy revving, then it had still pulled forward for a while, weakly and
intermittently, until it came to a complete stop, never to move again.

A few mechanics looked at it, and they said it was automatic gearbox
failure.  Others said it was the electromagnetic clutch embedded in it.  
Either way they wouldn't repair it.  There is a company in Leatherhead,
Hardy Engineering, who would repair it, but at a cost of approximately
£1,000.  In my opinion, that's quite costly, and I'd rather buy another
used car with that money, even perhaps something other than a Punto.

Most mechanics we've seen, not even want to change my gearbox for a
salvaged one I could buy from a scrape yard (quoted at £175 plus p/p);
those mechanics say that on top of the cost of the used gearbox, they'd
have to charge me for labour anyway --whether that works or not-- and as I
may altogether be spending about £500 (including labour, and towing the
car) and still not have my car repaired, they rather don't want to do it.  
Then there's the issue that most of those mechanics aren't Fiat
specialists, and I'm not sure how much of a Fiat specialist you need to be
in order to change a gearbox like these, and have it fitted properly.

To summarize, my options seem to be,
- Take it to Hardy's and spend £1000, which on the plus side is guaranteed;
- Spend about £500 fitting one bought from a scrapeyard (not guaranteed);
- Trying to sell the car as it is (not sure how much money I'd make?);
- Giving up the car to the Local Authority so that they get rid of it.

And there are some expenses "locked" in the car, as is almost a year's
worth of Road Tax and a valid MOT; about 4 months insurance; a resident's
parking permit; and the last service I had had done, which cost £300.

Can any one suggest what's the best thing to do in these circumstances?