Check to see if your internet provider or router already offer parental controls. More longterm - the Gryphon router with parental controls would give you control at a device level.
I collect all devices and keep them in my bedroom at night. Right now I've been keeping laptops and chromebooks downstairs, but I've also collected those when we've had problems. The most successful hiding place I have right now is the dirty clothes basket. Kids can be sneaky and it's so hard to keep on top of it sometimes.
Mom to Two Wild and Crazy Boys and One Sweet Baby Girl