Tall Larch. Advice on air layering please.

Hello all,
I came across this Larch at the weekend at my local garden centre. It is about 12 foot tall and I paid £8.00 for it (about $12). The trunk is about 2 inches across. I think I got a good deal and hope others agree.
I think that by air layering I could actually get about 4 worthwhile trees from it but I guess that's going to take time and at my age that is in short supply, lol.
So, do I just chop it into one good tree and still feel that I got a bargain? Or do I do one air layer and get two? Can I do more than one air layer at a time? If I do an air layer how long must the new tree establish before I do a second air layer?
Should I give the tree a year or two in the ground before air layering or can I just crack on?

For anyone around Lancaster or Preston it was at Barton Grange and they had at least two more at this price.

Any comments appreciated,
Cheers,
Ian.