My mums birthday is coming up and she recently upgraded her iPad to the 8th gen 10.2 model but her old cases don't fit. I said I would buy her a case before my siblings could but then I looked up cases and found out how exorbitant the prices are for no good reason (thanks Apple).
So what's a good keyboard case to get? She uses it on her lap like a keyboard so it needs to be able to sit flat (not have a kickstand or something like that) and being able to adjust the angle would be a bonus. She already has the magnetic keyboard so if there's any cases that have space for a keyboard but don't come with one, those would be great (I can buy a sheet of magnetic paper if it doesn't have magnets).
I bought the iPad 12 inch pro magic keyboard. It cost more than many people's laptops. But it's really high quality, it feels more like the built in Surface keyboard than anything, except more like a plate of steel wrapped in rubber. If you can't afford one then look at generic versions with a similar rugged rubber design, or even the plastic ones. If she types a lot on it then don't get her a bad cheap $20 BT keyboard for her $700 iPad. Get the better BT keyboard that you'd be happy to use all day yourself.