Dude decking is the easiest thing in the workd to do yourself - my mate got a quote to cost $15k and we did it in $3k (big area)

All you need is a flat surface - some do concrete slab but we just leveled the sand and comapcted it slightly with a water roller from kennards.

Then use treated pine for the box frame secured to your house with dynabolts etc..

Then get some nice decking wood and lay but LAY WITH SCREWS!!!!

Some use nails and over time they always under do... 3 years later and my mates hasent moved at all - takes a little longer to pre drill and tap out but well worth it!!

basic inst but u get the drift

Cheers

Chris