I'll jump in: about 10 years ago we added a ~400 sq ft deck to the back of our house. It has a small wing surrounding a hot tub and a small 8 x 8 wing for an outdoor grilling/bar area. It is elevated may 2.5' at the highest point - so not up on stilts. I managed to do the project with my wife and some help from neighbors. I'm no carpenter, but the ladies do find me handy (Red Green reference, anyone?).
Mine sits on deck blocks that are dug down a few inches sitting on gravel that is dug down and tamped still further. If I did it over I would do small piers for aesthetic reasons, but it looks fine.
We used treated lumber and composite deck boards. I do not bother lying to myself about my willingness to stain or treat the deck as often as I should (or keep dogs off it while doing so). So far, everything has held up great.
I planned everything out, went to a local lumber store with my sketch/plan who told me what I might want to change (this band needs to be bigger, consider this type of screw, etc.). Then placed the order for all needed materials: deck boards, deck blocks, various support boards, joist hangers, nails and screws. All dropped off in my driveway.
Dig the piers. Place the footers (be they deck blocks or otherwise). Then frame out the deck (outside and mid point bands to hang joists from), add the joist hangers/joists to make sure you meet the minimum spacing, add any stringers you need for strength (or to shore up spacing issues), and start decking.
I planned my deck to be the same length as the deck boards I bought, so it made fairly quick work. I had everything planned out before I started and a few tricks I learned as I went made it easy. I'd guess it took 30 hours of work from conception to completion - but there was no need to power through it day after day. A half finished deck can sit during the work week without much concern. Very little heavy lifting since you are building it in place stick by stick. Lots of bending/stooping as you nail joists/hangers or screw down decking boards. Otherwise, I think many people could pull it off that might not think they could. Could be a different story if there are physical or time limitations, or if the deck is in the air providing additional safety concerns.
I didn't realize that had been +/- 10 years and it has held up quite well.