This place was bigger and better than we expected. The place is a big three bedroom, two bathroom, through-house apartment in the second floor. There was good to cook food in the kitchen as there is a gas stove with oven.
The host Manuela is really nice and helpful. She is fluent in english and lives in another flat in the same building, so it was very easy to ask her if we needed something.
The aparment is located in Marsalforn, which had almost all the services we needed. There's a dive shop few doors down the street. A bike rental with mountainbikes is a few hundred meters from the apartment. There is a small supermarket nearby and larger, cheaper supermarkets at about 10 minutes walk away. When we wanted to go to Victoria to even bigger supermarkets or to a fish shop, we used a bus. The bus costs 1,5 euro (during winter) and the stops in front of the house.
There are lot of places to go snorkeling in the Marsalforn area. My favourite was Xwejni bay, where the water was clear and and plenty of fish and other sealife. There was even some bristleworms crawling on the bottom.
We saw also jellyfish in the area. At first we were worried about all of them. However after visiting a dive shop, we knew which were harmless and which were the nasty ones so we did not have to get scared of the nice ones. If you like to research before you go, you can find online the ioi-kids "spot the jellyfish" -project, which has info and images of the jellyfish.
I am really happy, that we chose to stay at Manuela's place. The apartment suited us well and was located in a good spot.