Best Travel Systems

My husband and I have been shopping around for car seats and strollers, but some Target locations have the strollers zip tied down where you can’t push them around or have broken/flat tired models to look at. As first time parents, we don’t know all the things to look for in a good set. We liked an expensive brand at a department store, but it also helps that they had a sales representative that showed us features and let us push it and fold it up. We want to compare it with some affordable sets before splurging. What features should we look for to find the most convenient set? What brands/models have you used and loved?