I was a solo traveler however the apartment could comfortable host 3 people; 4 at a push.
The kitchen is well equipped, the shower slightly small [I am 5' 9" tall and about 71kg and I found it a little cramp at times] but it has two options; a fixed head and a shower hose which does help make up for a slight lack of space.
The apartment is a 4 minute "brisk" walk from the beach, or 7 minutes if you take your time, which is a major plus, there's also a 24 hour pharmacy about 50 meters from the front of the building, and various convenience stores, eateries and bars within a short walking distance; if you don't want to eat in the beach area.
There are plenty of travel options into the city center; with buses, trams and connecting metro stations all within short travelling distances from the apartment.
There is no lift in the building, so if you struggle with stairs I would say that this apartment may not be for you; it's approximately 6 medium flights of stairs from the ground floor to the apartment [it would take a fit person about a minute to climb].
All in all, I would say that the apartment is a bargain, especially if there's 3 or 4 of you staying there, and I would definitely consider staying there again; especially for the proximity to the beach and the comfortable mattress.