We had a great time at Meelu's apartment. Very clean with tasteful decor and furniture and had all the amenities in an actual house -- including a real functioning kitchen (with oil! though we didn't cook) and washing machine. Meelu was also responsive and gave us some recommendations on eateries in Beitou.
Though it's on the pricier side for Taipei, it's pretty worth it for the hot spring and the amenities provided. Though it's much nearer (~3 mins walk) to Xin Beitou MRT, I suggest walking from Beitou MRT (~10 mins) in the morning/evenings if you have the time. You'll pass by plenty of food stalls and you get a great local residential vibe from this side. It's also convenient (direct bus from Beitou MRT) to get to Yangmingshan if you're into nature!
Overall, we enjoyed every moment here and would return again :-)