Facts about goats:
1/they browse on weeds and shit. they dont eat much grass. They are bad lawn mowers.
My garden is mainly weeds and shit. Sounds ideal 
2/They climb, through, over and under fences, if you want to find them where you left them, you need to nail their feet to the ground. Mmmm, could be an issue.....we do live in a mid terrace house with no back entrance for quite a few houses either way. Any idea how many fences it would climb through?
3/The males smell. A lot.
We have a spaniel cross. I'm game for anything.
4/The females need to be bred to make milk. That means an extra goat every year. Half of them will be boys, who smell. A lot. This could be an issue. Maybe I will get an ex-breeding goat, a bit like a rescue dog.
5/The females produce shit loads of milk. Excellent. I won't have to keep driving two miles to the One Stop because DH has used it all again. I can reply to "We've run out of milk" with, "the goat's in the garden..." 
6/The males have only two uses: a/smelly lawn ornaments, b/goat curry. We can't eat goat curry, lovely though it may be, as DD2 is veggie. Will have to stick to the ex-breeding female.
7/They need to live in pairs. I think I satisfactorily ascertained up thread (with varying levels of agreement, but never mind) that our dog looks close enough to a goat to fool the goat.
8/They shit, everywhere. As does DH. Well, not everywhere.....
9/They have horns and they headbutt. They headbutt with horns! My goat will be a perfect specimen of excellent goatly behaviour, just like my children, dogs and husband (ignores howls of laughter in the background)
10/They dont have wool. That's OK, we can knit our sheltie.
11/They dont lay eggs. This is disappointing. I was hoping they did.
Still want your free goats?? On balance, I think so, though I am still considering sending my bank details to the obviously-trustworthy-and-not-pulling-a-scam DBF for the tapir.