Realistic Styrofoam Tombstones (Tutorial)

EDIT: I bought the styrofoam second-hand on Facebook Marketplace.
You can get the same sheets at big box hardware stores (just not for that price).
This was pre-covid, so the prices of building materials hadn't skyrocketed yet.
But don't forget: any styofoam will work, and it's often seen as a waste material, discarded with large furniture etc purchases. If one is really keen, it's possible to source styrofoam for free, from places like furniture stores that unpack a lot of things regularly.
Step by step instructions for how I made my spooky Halloween "Pet Cemetery" tombstones.
Styrofoam is dissolved by most spray paints, so the easiest choice was to paint it with regular wall paint (Behr in this case). I didn't want to spend a lot of money, so I checked the hardware store over time and collected some "mis-tint" unwanted cans for cheap (eg. $4 a can), and I think also had some paint left over from around the house. I touch on this in the video, but forgot to explicitly explain it :)
The tombstones were a huge hit at Halloween!
For the overall decor, the idea was to make a creepy, unkempt cemetery, with dead flowers, religious candles, and crooked fences. We hadn't planted any perennials yet so it worked. This year I'll be going for a more robust, Victorian set up since we have some plants in the yard now.