Nissan Largo Friends

Hi folks .. my partner and I have just bought a Nissan Largo .. so excited and can't wait to pick it up on Thursday. We both have a couple of questions about it ... where can we get an awning and we noticed when we viewed it that the alarm would go off if the doors were open any length of time. I think maybe the garage owner was pressing the wrong buttons on the key fob but we hate to think we can't have the sliding door open without the alarm going off all the time. Any clues please .. thank you in advance ..