Actually, you know, you just need #1 if you're hiring people who aren't in their early 20s, or something. Most "help us solve hard problems!" technology firms/startups in London simply don't pay that well, and that makes it hard to attract the older, experienced developers with families.

Hiring contractors is another way of quickly getting access to a very large pool of skilled workers, but I find that most smaller companies never bother, even though the TOC of having a contractor on board may not be all that much more than a permanent employee.