I'm looking for a qualified tradesperson to unblock a stubborn kitchen sink drain in my flat in the UK. The blockage started a few days ago and now the sink is draining very slowly, with water backing up into the other basin. No strange smells, and there’s no visible leak. I’d prefer a skilled plumber or handyman who can diagnose the cause (hair, grease, food waste, or a partial blockage) and clear it safely. If needed, I’m open to temporary fixes or guidance to prevent future issues. Please bring basic tools, use clean practicable methods, and share an upfront estimate for the work. Accessibility: no exterior access issues, parking available nearby.