We stayed in a studio apartment for 4 nights during Sitges Carnival in Feb, the apartment itself couldn't be faulted. Checking in using the ATM style self check in was different but worked ok, although as you have to pay the city tax by card we found we were charged by a bank for using our debit card abroad (not ideal as the charges were more than the city tax). Apartment was perfect with everything you need for your stay, washing machine, coffee machine with free pods available, beach towels, free water and cava in the fridge for your arrival, also a safe in the room.
The location of the apartment is easy to find if you head to the beach and walk to the large church on the seafront, the apartment is in the first road before the church (between 2 restaurants).
The downside of having the ground floor apartment is the noise from the street. The apartment is next to a bar/club that remains open till 3am and there is another bar almost opposite which also stays open till 3:30am, this means lots of people stood outside being very loud. We went during carnival week and found it was very hard to sleep.
Also the walls are thin therefore you can hear every time someone enters or leaves the apartments as the main door is behind your headboard and you have to slam the front door when leaving. You can also hear the apartment above.
Would we stay there again, absolutely but we would opt for a higher up non street facing apartment.
Overall an amazing apartment, well done