We didn't have the chance to meet eachother but the contact was good through messages. The apartment had a lot of space, was clean and was on a good location, near several busses and also on walking distance from the center (aboud 30 minutes). A tip on hot summer days (not with small kids) is to go to the Rhone and let yourself go with the flow of the river for a bit. If you want to do what the locals do, you can jump of the bridge into the Rhone. It's also really nice to swim in the lake, there is a good spot at parc de la perle du lac to go in the water and also to lie in the gras.
Thanks for everything!