Vacuum advice

Hello, I’ve been trying to help my parents purchase a new vacuum and I’m finding myself now lost and overwhelmed with the options. We’ve decided on a “for life” vacuum as we’ve done the Shark and Dyson’s who just give up after a few years. We have two dogs, a black lab and a golden retriever so you can imagine there’s lots of hair, and it becomes very visible. We have a relatively large two story home. The stairs and second floor are all covered in a dense medium pile carpet that seems to really trap in the dog hair (we often use brush/scrapes first extract dog hair before being able to vacuum). While the downstairs is mostly all hardwood flooring. We want to switch to bag vacuums, as the dust and hair flying everywhere with bagless is not ideal. We have been looking at Miele and Sebo’s but aren’t sure the best one with stairs, mixed flooring, AND pet hair. We’d love to have one that could do it all, but at this point the way the dog hair collects on the carpet, if we could only have one thing - it would be to take the dog hair out of the dense carpet especially on the stairs. Would the Sebo Felix be better because of the stairs or the Airbelt K3? At this point I’ve become pretty lost, any advice is appreciated!