Question to cyclists

So my best friend lives downtown. She is into biking around her neighbourhood. She recently moved in the area. Has a small grocery (mom-n-pop type) store. She just came from Amsterdam. Is looking for a bike to ride around. Does not want a car. anything outside downtown and she will TTC it. I am getting her a bike.

Now, I can put a basket/box/whatever thing for when she goes groceries or whatever shopping.

As far as I am aware, there are two options, in the front, and in the back (above the back wheel).

What are the disadvantages/advantages of each? What would you recommend?

The bike is a "it's your birthday and moving in/welcome back" type gift by the way.

Got a helmet, the lights, the vest. I even got a hamburger shaped bell. The most perfect bike for her.