I'm not a lawyer but I've seen, and paid for, my share of it, and one thing I know is that if you don't want your lawyers charging you don't fire off emails like; "Hey, if you know X off the top of your head, can you left me know about it?". You either need a legal answer, or you don't, otherwise you're wasting the lawyers time and your money. The law is complicated and convoluted and even things that seem simple can actually require lots of research.

If you're a young start-up, don't hire on WSGR, Orrick or their ilk - I know they're a status symbol, but they'll cost dearly (remember: deferred fees are still fees that need to be paid eventually). Most start-ups need some corporate, a little employment and maybe some patent/ip work. There are lots of small firms that specialize in that, especially in the tech hubs. If you need more specialized work, hire in a firm that specializes in that. Smaller firms usually offer better service, at lower prices - you'll pay a lot less and work with experienced partners rather than 1st year associates.

Finally, your lawyer is not an employee, firing them off an "urgent" email at 4pm on Friday means that you probably won't get a response until Monday, and probably won't get an answer until Tuesday. Just because you work on the weekends doesn't mean that they do. Don't leave important legal questions until the last minute and you'll have a much better experience.