I already have a Schengen visa when I applied I had hotel booked for the full length of my stay. I found a deal with an apartment through airbnb.com and booked the apartment and the hotel (about half the time on each). Will I have issues with immigration? What should I put on the immigration form?

My main concern is whether it is a problem to book two separate accommodations in the same country? Also since the first accommodation is an apartment rental will I have any issues with immigration?