My two friends and I stayed at Lotje's place for six days in May 2015. We really enjoyed our stay.
The apartment is very nice, clean and comfortable. There is a tram stop very close by which takes you directly to Amsterdam Centraal or Dam Square in ten minutes. There is a large grocery store less than a five minute walk away which has everything you could need. There are also a number of nice bars and restaurants within walking distance of the apartment.
Lotje provided us with a guide containing clear instructions for how to use the appliances in the apartment and we were able to do so without any trouble. The wifi signal was strong and the terrace was lovely, we only wished it had been warmer during our stay so we could have spent more time out there.
We did not have a chance to meet Lotje in person but she had a friend meet us for check in and she was in regular contact with us via text (SMS).
If you're looking for a place to stay in Amsterdam, I'd highly recommend Lotje's place!