Motorise window blind IKEA Fridans.

I'm not making a detailed guide so make at your own risk.

Fits the standard cheapo gear motors. You will need to cut the shaft.

You will need to disassemble the blind to replace the handle with a gear. It's tricky because it's not meant to be taken apart, but it's possible. If you manage that, then it does no permanent damage and is fully reversible.

You will need to make your own electronics to control the motor in two directions. I used wireless quad relais board.