Bathroom caulking and repairs in Toronto usually start with the same sight: a black line along the top of the tub that no cleaner will shift. Once silicone lets go, water gets behind it, and scrubbing only spreads the stain. I cut the old bead right out, dry the joint, and lay a fresh one.
Old houses here often have tile set in a mortar bed, so a loose tile needs bedding rather than a smear of adhesive. Downtown condo bathrooms have no window at all. I also regrout, refit grab rails and swap tired exhaust fans while I am there.