The excellent Logitech Create keyboard for the iPad Pro that I reviewed last month is on sale for $70. From my earlier review:
The Logitech Create iPad Pro keyboard (on sale for $81 on Amazon) has changed the way I use my iPad. Mainly, I'm using my iPad much more often, now that I can enter text with a keyboard. If I'm on a short trip, I'll often take it with me instead of my bulkier MacBook Pro. It works well with Google Docs, which is how I do most of my work.
It has a backlit keyboard, which is essential. The keyboard is smaller than a standard keyboard, but it's not so cramped that I resent it when I have to do a lot of writing. I appreciate that it is powered directly from the iPad Pro via the Apple smart connector, because I don't need to remember to charge it. It also doesn't need Bluetooth pairing -- just insert the iPad into the case and start using it.
The top row of keys have controls for common things like one-tap to home, screen brightness adjustment, search, language switch, keyboard backlighting adjustment, media controls, volume controls, iPad on/off sleep/wake.
The case itself is textured so it won't slip easily when I carry it, and when closed the entire iPad is protected.
It's surprisingly thin and light, too. I wish I'd started using it sooner!