Mary's apartment was extremely convenient. Above tsui wah and right outside Yau Ma Tei A1 exit. The check in instructions were very clear with photos showing you the entrance to the building and step by step showing you how to get to the front door. The space was a good size for 3 of us though can imagine it's a tight squeeze if you have lots of larger luggages/more than 4 people. The apartment looks newly renovated and well equipped, inc hair dryer and iron provided. Hassle free self check in/out. Lots of eateries, supermarkets, 7-11 and plenty of shops downstairs and nearby.
One thing to note is that it is a rooftop apartment so you would need to walk up another 2x short flight of steps from the top floor to get to apartment. The steps /corridor do look a little dated but doesn't reflect how the apartment is at all.