If you're visiting Riga, I can't recommend Aigar's flat enough. It's well equipped, quiet, peaceful and comfortable. The flat is close to some local restaurants and supermarkets, and the tram is just a few minutes away so you can be in the old town in minutes. Aigars is a great host and the airport pickup/dropoff was all perfect.
Riga itself is a beautiful city with so much to do, we had a 3 day trip and didn't manage to see everything. Highlights were the art nouveau district, central markets and old town itself. I recommend the Riga pass for the walking tour, bus tour and the free use of the tram.