Do you know the height of the roof in metres? If it’s a self-erection (oo-er), make sure you’ve got space for the outriggers and don’t have it up in high winds. Obvious stuff but I’ve seen normal scaffold come down when it’s squashed up against a house and not braced properly.
There's a front garden that a tower should fit in, might look into DIY inspection.
Weird thing is it hasn't leaked since last weekend...