There is little that I need add to the previous reviews except for a different perspective. The two apartments housed in total 12 of my family, including two small kids, over 10 days for a family event in Basel.
The location is superb: a quieter street less than 5 minutes from trams and buses that take you directly to the main conference (Messe) area, the main railway station and the city centre (both hubs).
Our hosts welcomed the family warmly and openly and gave the kind of service, support and friendly inclusion that a hotel could never hope to offer, sharing their own living space and infrastructure without a thought.
Diamond people, quirky, smart and functional apartments, an all-round winner.
Notes: free city travel pass; grocers, takeaways, restaurants, pubs and parks very local; non-smoking house but balcony and covered garden area available; very fair price; weekly standard rent period, contact for special cases; English spoken.

We are just back from a week stay at Guesthouse Basel. This is a great find and a great place to stay. We travel to Basel for medical purposes and this apartment just makes our stay so much better. We love Basel but feel to confined in a hotel (have stayed at The Rochat and the University Hostel) in the past but like the idea that we have room to move around and the ability to cook our own food.
The apartment is as described in the previous review and the pictures that are on their website accurately show the unit. We found this to be such a joy to stay here and we are planning on staying here again. The apartment is very spacious, clean and compfy beds. It has everything that you could possibly need for a short or extended stay including WiFi. The only wierd thing is that the dedicated bathroom is down the hall, which really is no big deal. The building is over 100 years old and the floors do creak when you walk but you don't hear it above or below you, just in your own area.
The Landlords are very nice people and the landlady speaks very good english so it is easy to make reservations and to communicate with them. There is another apartment on the first floor that they also rent out. While we did not see it from the inside, the footprint seems to be about the same with the elimination of the little small (half) room with the bunk beds, otherwise it has the same basic size. Next trip we will try to take a look.
Anyone who is traveling to Basel for any purpose should consider staying here. It is so convient to the tram line #3 or 1 and the city center is very easily reached in a short period of time. The neighborhood is a very quiet residential area with little and big grocery stores nearby. There is also a Domino's pizza just near the tram line. This is the only American style pizza we found and it taste better than in the states. The pepperoni is a little different but the closest thing to what we are use to by far.
Guesthouse Basel is a great find and you won't be dissapointed if you stay here, it really is like a little home away from home.

My husband, son, and I found this a wonderfully convenient and comfortable place to stay in Basel. We had three nights after arriving from the states before we could get into a ski apartment, and thought Basel would be fun to see.
The unit is the second floor of a house; the young family hosts live upstairs. They were very pleasant and helpful, both in giving advice about the city and in providing things we needed. There are three and a half rooms: a private bedroom with a queen bed, a very large room with a king bed at one end and a living/sitting area at the other, and (the "half") a small room off of this with bunk beds. The third, fairly large, room has the shower and kitchenette facilities, plus a dresser. The w.c. is in the hallway, but private for this apartment. The decor is IKEA artistic, with paintings, small lights on a chandelier -- modern and homey at the same time. The beds and bedding were comfortable, and everything was impeccably clean.
The location was great. Although this property is not in the old city, it is a very short walk to the tram and then a very short ride to the old city, or from a different stop to the zoo or to the train station. The neighborhood is a pleasant residential area.

We would happily stay here again.