It does look like plastic.
Re: Paint supplies
There are two paint rolling trays pictured; one atop the paint can and the other shown in the lower right corner of the garage shoe pic.
One of the garage photos shows a brown patch where fresh paint was applied in an attempt to cover up evidence from the alleged crime, investigators said. That piece of wall has since been removed and seized as evidence.
http://www.wral.com/news/local/story/2338335/
“Charred human remains of an adult and a fetus were unearthed,” the statement read. “There appeared to be the bodies of an adult female with a fetus located near the abdomen region of the female.”
Authorities also released images from inside the Laurean house, including the garage where they believe the murder took place “based on the blood and the interpretation of the blood spatters” on the walls. The photos show a paint tray and 2-foot square patch of wall that has been repainted.
http://abcnews.go.com/US/story?id=4170769&page=1