I wouldn’t worry too much about the cost per se as it’s impossible to judge whether or price will go up or down in the next couple of years. However, getting an IS or any Lexus is a no brainer especially if you want to keep it for a while. They’re comfortable, quality and reliable. Take a test drive and if you like it buy it. You’re almost guaranteed it won’t go wrong as long as you look after it and get it serviced regularly.