It's not the size of your deck that matters, but what you do with it.

And today, I sealed mine.
Today was the first weekend with no rain for two weeks.  Not sure I really wanted to seal my deck on a holiday weekend, but what the hell.  I have vowed to keep this deck in great shape and it starts now.
What did I use?
ReadySeal.  http://www.readyseal.com/
"Natural Cedar"
I did a bunch of research trying to find the right stuff.  This stuff looked to fit the bill.  I could bore you with reasons but turns out you can do a quick search on the "best deck seal/stain" and get more confusing opinions then you can handle.  It seems asking this question is like asking what political party is best, ford vs chevy, oil changes 3k or 5k,  Bud lite vs Miller lite, etc...
After enough open minded research, Ready Seal shined through.
My wife and son came out and helped and what help they were!  They probably saved me a couple hours.
For those that wonder, I used every last drop of two gallons.  I have a 14'x12' deck about 10' off the ground.  If it wasn't for all those damned stairs, I would have had plenty.  As it stands, I still need to seal 2 sides of the 6"x6" support posts and the joists below.  But all the verticals and horizontals that matter are covered.

start 'em young

Always happy to help.  He's a great kid.

Somebody wanted to come out and help too.

Done

Almost done and still smiling.

another "done" pic.