We stayed in Dar Daheb for 3 days and were super happy with such a big house. The location is perfect; it is reachable by taxi and it takes a 5 minute walk to reach the medina. We were picked up at the airport and the rest also went smoothly: we met someone who would guide us the next day and we were picked up at the street by Rachid, he and his wife Amina manage the house. The don't speak English though, only French and Arabic.
The house is very nice, the overview on the terrace is even nicer. We loved the 'synchronized' prayers that came out of the mosques 5 times a day, while standing on the terrace. Some negative points on the house though: the internet is kind of slow (adsl, but i guess that's inherent in the location), the matrasses are a bit hard to sleep on and we didn't have warm water for one day because the gas bottle was empty. Luckily, this was solved the next day by Amina. Also, the house could only be reached by walking through some small passages; it was kind of funny that one kid wanted to guide us to our own house (with only 40 meters to go) and became mad when we didn't give him money for that.
Regarding the Medina, prepare yourself that this will happen on a regular basis; people wanting to guide you to your 'destination' and expecting money for that. Some people turned out to be very persistent (and annoying) with that, even if we clearly said 'non, merci!'. But you will get used to it. In one instance it was even convenient, when the waiter of a restaurant guided me (i was on my own) back to Dar Daheb. You will know the way after a while, but some alleys just don't feel save when it's dark.
Apart from that, the Medina (with thousands and thousands of little shops) is great, we never experienced something like that. A tip: i heard that you will only get a good bargain when you are accompanied by a local (guide). On our own, we couldn't get the price that we wanted (for a lamp in our case), they would only drop for like 10%. By the way, a guide for the first or second day is surely recommendable! Another tip: watch out when eating in Ville Nouvelle, we ate in some general 'snackbar' (salad, pizza and a hamburger), but my friend got sick the next day. It could be a unrelated, but the food there also didn't taste good at all. Eating in the Medina was much better, i loved the tajine dish that we got.