Try for a SEBO Auto X7 instead, since it’s a lot more compact and can work on plush carpets. If you’re looking for an immediate fix for your Airbelt E3, you can try this.

There's no point in having an air purifier if you're going to leave your window open for a significant amount of time. It'll be as effective as trying to refrigerate food with the refrigerator door open.

SEBO Airbelt E3, because SEBO as a vacuum brand is one of the more repair-friendly ones, and one of the reasons why I decided to go with it over Miele. It also has a decent selection of attachments that you can choose from, if you want to add onto the existing ones you get. Kirby upright vacuums are extremely sturdy, but they likely don't have the attachments you want.

I think the SEBO X4 or X7 are probably my favorite vacuums. They're compact, relatively light, and more easily maintained than Miele vacuums.