The decking material seems to be Brazilian Walnut AKA IPE, it is a more expensive material but long lasting, hard wearing and it does not splinter much because it is so dense. It is very dense so it will dull blades faster.
The railing has a IPE cap and the rails look like painted wood based on the attachment method at the bottom. The lower section looks to be about 40 boards wide which is about 20’ so I would guesstimate the SF to be 800-1000 sf maybe larger.
The rail cap costs about $7 per foot, the decking is about $6-10 per foot depending on thickness, the supports would be centered on 24” so you have at least 20 supports maybe $20+ each, rim supports, railing, screws etc
Materials cost;
Maybe $3-5K for the railing
Maybe $12-15K for the decking
Maybe $1-2K in supports
About $100 in screws
Maybe $500 in stain (stain for IPE is expensive)
Now if you want someone to install it for you double the material cost and add a bit because of the complex installation (on angle)
That comes to about $50K for a deck about 20’X40’ much of that is because of the material choice IPE is not cheap but beautiful and that is a HUGE deck.
If you really are looking to do a project like that you may be well served trying to find a wholesaler who can sell the decking etc to you for a discount because of the huge quantity, then hire someone to assist you or to install the deck, someone may be willing to do it for $5-10 per SF instead of the $30+ per SF in the above idea. Or you can use cedar which is an amazing choice for decks and stain it to give you the look of this deck for MUCH less.
The other point is that the arbor over the deck could cost you a good chunk as well.
It is sickening how fast a deck can become super expensive. I am working on a 12 X 20 deck now, just cedar and simple it came to about $5K, materials about half that. It was just the decking not the supports.
Good luck on your project, deals can be found if you try hard enough.
-Ryan