You will need (local lowes prices here)
Washer tray 25 dollars for a 29x31 (they had a larger one for 10 more)
Ceiling grate thing 9 bucks.. in lumber area with ceiling tiles
Zip Ties - 100 for 4 bucks
Astro turf stuff. Heres where it gets iffy.. they have green, blue and grey... they have thick and course, or smooth and soft. I chose the thick because I did not want to have any association with carpet at all. Grey was only because eventually it will go on my porch and i want it to blend a little bit. The underneath was also made like regular carpet so it eliminated the need to pop hole for drainage unlike the base of the green stuff which was more grass like.
The grey astroturf stuff cost me 4 bucks a linear foot and I got 2 feet (2'x6' gives me 2 extra squares for later)
Total cost around 41 dollars