20 year old student, looking for accommodation in Madrid

Hola!! Soy estudiante de Berlin y voy a estudiar en Madrid para un semestre. My spanish is not very good and I am hoping to improve it during my stay! As well as soaking up the flair of beautiful Madrid and its people. My budget for a room is quite low, as I don't need a big room or any luxuries to be happy. I much prefer spending my time outside, exploring and having fun with friends. The only thing I definitely need is wifi and allowance to have overnight visitors, as my boyfriend will come visit me sometimes:) I lived in a shared flat the last year, so know the ins and outs of keeping my room/the shared areas tidy and living with new people. I hope I can appeal to somone out there and would love to hear from you!

Greetings, Juliaxxx