Lovely and comfortable apartment in a great part of Madrid. We were able to walk almost everything from this apartment. We never met Marta and Paul, but Josep was very nice and easy to deal with.
One thing I will say is the late check-in fee may be clearly listed but for me it seemed excessive. Josep admitted that he lived nearby and literally all he had to do was drop the key off to us. With all the other drop off options available (this is actually the first Airbnb I have had in awhile with an in-person check-in), I did not get a lot of value out of this.
Otherwise, lovely place to stay and there were no problem.