Our trip to lille was on the cheap, this was the cheapest place we could find between 4 of us working out at just £12pppn, which is cheaper than the youth hosel. It boasts a living area with double sofa bed, TV and internet connection. A small kitchen/dining area with cooking hob, utensels, microwave and a fridge. Up the very steep stairs to the bedroom with aple storage for your clothing there is a you get what you pay for double bed and a huge bathroom with bath vanity unit/sink and toilet.
For the price i have to say it was fantastic, 4 people could spend a few nights here without getting on top of each other. It is only a 15min walk from Euralille but a metro stop is 100m away with lille Flanders only 2 stops down the line.
A Warning mind the reception is not 24hrs and closes at 7pm so if you are not checking in before then make sure you let them know.