The joists will be pressure treated SYP, not cedar. It doesn't sound like you've done enough research to even understand the construction material aspect of the project. And this is the easiest part.
Extremely doubtful the building phase will go well.
People get killed when decks 10 feet off the ground fail.
Ron

wow - harsh response to a well intentioned post asking for assistance. i don't have the knowledge to help you out patches, but i'm sure there will be others here who can steer you in the right direction in a more helpful manner - i hope!! don't let this sour you on the gardenweb forums here.

http://deck-lok.com/

We have a tiny "deck" and are using them - use them if you are building one that high. They are about $10 each, but worth every penny. Get a good deck building book and have lots of patience. Framing our 52 inch by 52 inch deck an foot or two off the ground too us a weekend and we still have a little more to go - we did it right, and it's not hard to do, but if you haven't done it nor have anyone helping, it takes a lot of time.

For the Fiberon Tropics Mahogany we were quoted $2.64/contractors price at two lumber stores, not including screws, etc. Plus you need, framing, concrete, all the other brackets, screws, bolts, copper flashing, tools (if you don't have them or can borrow them), etc.

I think we are switching to IPE as the Fiberon scratched and it and Trex are the only two with the very dark color and I think Trex looks too much like poop (sorry, don't know how else to describe it). And, that runs anywhere from $1.50 (not including shipping) - $3.00/locally.

I forget how much or pressure treated wood cost. It was probably about $1 a foot or so but you have to buy the lenghts they have so don't forget to factor in overage (same with the deck boards).

The guys here are helpful with very specific questions that haven't been asked before or are specific to you - they don't like very general questions if you haven't done your homework - they are busy and tired as it is decking season for them. And to give them credit after starting our tiny deck, it's a lot of work, especially if you do it day in and day out with picky customers and that doesn't include any of the other business aspects.

This DIY "deck" is costing us much more than we thought, but given what we had, worth every penny. (and my husband is doing an amazing job).

Many things are easy if you do it every day. I have seen some Folks over here do some really nice projects with out the aid of a Deck Contractor.

Of course skill leavel has to factor into that as well as the right tools and the amount of time/work a person has with them.

Ol Ron has a point its a good idea not to use cedar for your framing .40 preasure treated material is a good choice.

Projects that high up usually require a stairway but say your not planing one. Around 430 sq ft just material sitting in the lumber yard not including a permit with in the guidelines you have given. hmmmm from $18 to $25 a sq ft.

Ron is also correct with the danger area agreed on with a project that high up not just to you as the building goes on,the living things around you and the danger of failure from faulty footing and ledger conections down the road. J

Thanks for the advice. Yes, I know to use pt for the posts...too fast in typing and no proofreading. I am replacing a very very poorly built deck that was built by a contractor. I should take some pics of it and post just for fun. I fear it will fall down and its only 7 years old. I tried to have them contractor fix it in the beginning and they couldn't or wouldn't. The shoddy new construction in my area that is accepted as "normal" is amazing. But, that is an entirely different topic. I mostly was trying to get a sense of the budget. If its $30 a sqft DIY, then I can't do it this summer. If its closer to $10 - $15 sqft then this summer is a go. I will have stairs...my lot slopes front to back, and this deck will be L shaped. On one side its only a few feet to the ground, so the stairs will go there.

What are your thoughts on building the deck completely freestanding as oppossed to ledger attachment (this is one reason the contractor deck will be demolished...its attached incorrectly and no flashing was used). I have seen some sources suggest that approach. I haven't started researching yet as I need to figure out if its in budget.

Regardless, I will research deck construction completely before starting. One of the main reasons besides $$$ I want to DIY is that I want it done correctly. Obviously on this board there are several wonderful pros. Unfortunately in my area I have been disappointed each time I have hired someone. Even with referals etc.

So, for those of you who have used composite, I would love to know the budget per sq ft.

Decks that are freestanding, that far off the ground will require more cross bracing then one attached to the house. There's no reason to go this route unless you're not versed in proper flashing details to protect both the house and the deck structure.
Cost per sq ft requires a plan and a local trip to suppliers to see their costs. Also the deck choice you're making. Be aware that the way you choose to run the decking will determine the substructure detail.
Composite decking also has the problem of being too hot to walk on or sit on due to heat gain from the sun. Overhead shade and deck orientation will modify that.
Ron

Good composite should run about $6 per square foot.
Although neither of us are fans of Lowe's or HD, one thing you can do is go there, particularly with a simple deck like yours, and get a deck design and pick list. Then take that to a real lumberyard, and you will have your price.
What are you going to use for a handrail? Even if you build the railing out of wood, I suggest a composite cap rail - kids tend to run their hands along the top of a railing and this makes it splinter free. Might tie the look together a bit too. Or, you can get composite 2x4's that look great with the black aluminum balusters.