Single Wall vent pipe question

I believe that this is the incorrect type of pipe for the furnace exhaust. It is single wall with a split seam.
This is a flip house. The listing agent/flipper/owner didn’t pull permits.
The buyer (my client) walked. Seller is pissed? Go figure…
Thanks!

The furnace is new!

Also the water heater is a death trap!

Why do you believe the single wall pipe is incorrect? If appropriate for the furnace, it can be used but must maintain a 6" clearance to combustibles.

looks like who ever was doing job never finished job, for what ever reason, looks like the w/h pipe in back ground, behind w/h

Nice notch out on floor joist too.

I see more things than single wall flue pipe to write up. Furnace sitting on concrete basement floor should have been elevated. Supply and return air duct traveling in non-conditioned spaces are required to be insulated.