Regarding the next edition, do you have planned to book the accomodation now? I have seen that there are only a couple of apartments available on Booking and Airbnb near the poligono Marconi, so I think it is a good idea to book it now. Otherwise, I have not clearly understood how to reach this poligono Marconi by public transport: the closer metro station is Villaverde Alto, that is very far from the airport and you need to change the metro line first in Nuevos Ministerios (from the pink one to the blue one), and then in Plaza de Espana (from the blue one to the yellow one), so the trip by metro seems to be over one hour long. It is also possible to reach the poligono Marconi by train, but I do not know how the trains work in Spain and where is the closer train station to the airport