Jiris apartment is a great place to stay for a short trip in Prague! I would definitely recommend it. You can reach everything by foot, the old town, Charles Bridge etc. Right by the apartment are small markets where you can get daily needs like water and also different restaurants and fast food. We shared our apartment with a nice other couple, there where no difficulties with sharing the apartment. One weird thing: the toilet is separated from the rest of the bathroom. The sink, and bathtub is in another room. A shower curtain and a holder for the shower head might make sense...
The communication with Jiri was super easy. We flu back in the evening but we could leave our bags in the apartment and could still use it, which was really helpful!
Overall: would book it again!