Cheapest way to clean air fryer?

Unplug it, let it cool, basket into hot water with washing up liquid and leave it to soak. That's free and does most of the work. Stuck bits, bicarb and a splash of water as a paste on a soft brush - nothing abrasive on the nonstick. The element needs a wipe from underneath with a damp cloth too, that's where the smoke smell comes from.