I'm quite pleased with myself
On Sunday, and the following Monday is a public holiday, the sewage got blocked at a rental house of mine. Tenants phoned and said one of the toilets was blocked. It turned out it was the sewage pipe from the whole house and blocked under the driveway or where it joins the main (city) sewage pipe.
A few years ago I bought one of those drain unblocking tools. Looks like a spool of one inch wide coiled spring. So down the maintenance hatch it went and I found the blockage at about 10 meters. With the auger fitting on the end and the electric drill spinning it at my end, it cleared it.
A very satisfying suction/vacume sound at all the water poo and paper disappeared.
All these tools I buy just in case I may need them... Well sometimes I do.