Wonderful stay!
Staying with Bas is very easy. He's easy to communicate with, and flexible with your arrival. We were able to drop our bags when we arrived in the morning before heading out. Bas finished up at the apartment during our lunch and we came back at 14:00 to an apartment in mint condition.
We were three adults and one toddler, which worked like a charm. The stairs from the street up to the apartment are a little steep, but we managed lifting the stroller upstairs as well without any big trouble.
Don't bother buying a tram card, the apartment is central enough to everything you want to see!