Cheap Endoscope for drain issues and drain unblocking

[@fat_tommo_goes_boating]

We often get a blocked drain, it's where two toilets meet. I now have a "poo hose" shove tge hose down the pipe with the tap turned full on and it clears every time. I usually have to do it once a year, I assume it's how the pipes are joined or the shape of the joint