Should I shut off the main myself?
If you can’t isolate it right at the fixture, yes — use the main, but only if you can reach and work it safely.
Why does this drain keep clogging?
Repeat trouble usually points past the trap — check the branch line, the vent, and the slope before assuming it’s simple.
How do I choose tank or tankless?
It comes down to how much hot water runs at once, what’s already piped for fuel and venting, and what the panel can spare.
Do old pipes always need full replacement?
Not necessarily — material, pressure, leak history, and how hard the section is to reach all factor into a targeted fix versus a full repipe.
Who checks the provider’s license?
That’s the homeowner’s job — confirm credentials, insurance, permits, and warranty terms before authorizing anything.