An Eleganza is a kind of limited edition, but only in so far as a few extra painted bits and wheel trims.
Like the Bianca, I think it had painted bumpers and door mirrors.
All it really is though, is a 45S with a few extra painted bits.
It's not worth any more or less than a standard Uno, as by the age most mk1's are it's all down to condition rather than specification.
If it's a good one, don't worry about how much it's worth. Just enjoy it!