Do a search, because someone (Tboneal?) was asking about deck stains and I copied all the stuff out of consumer reports on what was best.
The short answer is that its a time consuming pain in the butt. I just did a few hundred feet and used a composition board I got from Lowes for $3.39 a board...not much more expensive than redwood and it looks great.
Very realistic and inexpensive for a composition board.
To be a little more helpful to your situation, you're going to want to let the wood 'dry' for a few months before applying a stain to it. The amount is going to be wildly different depending on the type of stain used, the woods dryness, and how you put it on. Its an easy DIY job...I'd get one of those $5-6 two quart pump sprayers in the garden section, lay out some paper or drop cloth and spray it on with that, and have someone walk along behind you with a roller and a brush to give it a little working in. It'll go pretty fast.
You'll probably have to do it every 4-6 years.
Some folks get by for 20 years without ever staining the fence, but IMO it looks crappy after a year or two.
Be fearful when others are greedy, and greedy when others are fearful. Just another form of "buy low, sell high" for those who have trouble with things. This rule is not universal. Do not buy a 1973 Pinto because everyone else is afraid of it.