Let me explain this in leighman's terms...
I think that sephiroth may have been talking about buying 30 or so santas
You are talking about buying lots of santas, and that is were £1200 came from
to make a field
You would buy them in order to make a sup' air field
and afterwards he'd have an army of the little blighters to sit in his backyard
When you had finished with this, you would have 30 or so santas in your garden, thus making an army of inflatable santa's to sit in your garden.
Not so hard, is it???