This apartment is great for those willing to experience the true value of Berlin. The area is perfect for walking around, getting great food and drinks, and just enjoying the vibe of Mitte / Prenzlauer Berg. It's hard to pick a better spot. I might be biased due to actually living in the area for two years, but still.
Martina is an amazing host, the real airbnb experience and not a rental agency that you'd usually get. She was super accommodating and helpful, so that's also something to cherish.
Her apartment is spacious, with two separate rooms providing great comfort and utility. Beds are large and comfortable, which is also quite rare.
The living room is also quite spacious, combined with decent kitchen and solid bathroom -> you get a good package for spending several days in Berlin, perhaps with a company of friends, which is rare for Berlin (finding a space that is). There's no washing machine, but there's a laundromat about 200m away, it has not been an issue for us at all.
It may not be 100% new and freshly renovated, but you do get the feeling of authenticity and like I said, location is hard to beat. The pricing was reasonable. Will definitely be staying at her place next time we come to Berlin.