We visited Arica with my 18 year old daughter and stayed 3 days in Alma Apartment. The property is very nice, with details in the decoration that make you feel comfortable, with lot of space available. The location is in Chinchorro beach, a little bit far from downttown, but Uber and taxis are very cheap and is easy to move around. The check in / check out process was OK, and they let us and early check in (thanks Marcela!).
Surely we'll visit again.
We slept only one night in the apartment. Nice, new, clean, well located.
The only downside, fifth floor and no elevator.