Marcia's apartment was wonderful for a weekend trip - spacious, well decorated, and well lit. It's a perfect space for a couple who wants to spend some time in the apartment itself. The building is stunningly beautiful and also has a staffed security desk. Marcia was very responsive over Airbnb and made sure that we'd be able to check in soon after our flights.
It's located in a bustling neighborhood (Centro), close to Palacio Bellas Artes, Templo Mayor, and a few other sights. We were easily able to walk to different neighborhoods, as well as take cheap Ubers to/from the airport, Coyocan, etc.
Note that the plumbing isn't what you might be expected to be - it works perfectly fine, but the shower has a lower water pressure than you might expect and you shouldnt throw too much TP in the toilet ;) There's also some street noise on the weekend. I was able to sleep through it easily but you might want to bring earplugs if you're a very light sleeper.