I have a small "powder room" in my house which is never used. All it has
is a toilet and sink. The water pipes to that room are disconnected.
There were some broken pipes when I got this home because the pipes had
frozen before I bought it. I replaced the pipes but not to that room,
because they are very long, and I saw no reason to need a powder room.
There are no kids, so the main bathroom is all thats needed.

In the meantime I always have small repair projects sitting on my
computer desk or the kitchen table. Rather than having those projects
laying around the house, I am thinking about turning that powder room
into a repair shop. It's a little small, but I can make it work.

Removing the sink is easy. Just remove the sink itself and cap the pvc
drain pipe. The cabinet under the sink will work well as a place to put
tools and parts, and a piece of plywood will make a good top to put my
projects.

The toilet is on the other side of the room. I want to remove that and
put some shelves there. But I dont want to remove the toilet flange (for
resale value, not to mention having to change the piping). I just want
to CAP that flange. It will be under the shelf, so appearance is not an
issue.

Do they make some sort of cap for a toilet flange? (It's PVC).
I suppose I could use plywood or metal, but I want it sealed properly so
sewer gas dont leak into the room, (or sewer water if there ever was a
backup). I did look at one of the "big box" home stores and did not see
anything. I imagine this is something I'll have to buy from an actual
plumbing store, or buy it online. (If such a thing exists).

Anyone know if there is something made for this, and what it's called?

Also, if I do have to make something, I'm sure some silicone caulk would
make a tight seal, but first I'd have to remove all of the old wax seal
residue. Is there some solvent or something that will remove that wax?