Franziskas house in my opinion is perfectly situated to those who will stay for about a week. you have the bus m85 that connects to a station with u-bahn subway or you can go through lichterfeld ost, to get there you can either walk, 20 min, or catch a bus m11, 5 min, then catch a s-bahn subway and get to the center of berlin. pretty fast in my opinion.
on regards to the house, its pretty cosy, confortable and with everything needed. perfect for a 1 week to 2 weeks vacation.
I didn't meet franziska but she was allways on time with a feedback to my questions.
I'd recommend Franziskas house to anyone who asks me.