Hi Lynley, Thank you for your enquiry. The Britax Parkway SGL does not have arm rests that adjust during installation. For further information on installation of car seats we would recommend contacting your nearest Baby On The Move store. Car installation is free at all our stores when a restraint is purchased with Baby On The Move. However Installation fees are at the franchisees/stores discretion when a customer has requested to price match or is looking to install a seat purchased elsewhere. Regarding suitability for your vehicle, sadly not all car seats fit all vehicles. There are many factors that affect a child restraint fitting a vehicle such as length of seat belt, position of seat belt buckle on a long stem, contours of vehicle seat, height of passenger and space allowed behind the seat for rear facing and size of child car seat may just be too big for the vehicle. Due to this we always recommend contacting your nearest store. If you follow the link https://www.babyonthemove.co.nz/store-locations/ this will take you to our online store finder where you can find contact details for your nearest Baby On The Move Store. Here, one of our expert Car Restraint Technicians can assist in helping you with finding the right car seat for you and your child and assist with installation. We hope this has helped with your query.