Have a family meeting - explain expectations clearly, explain the affect on you - listen to them as well, draw up a rota. Have defined boundaries - communal areas have to be kept cleaned up - their pits - they can live in their own squalor, my rule is if it belongs in the kitchen then it gets returned to the kitchen - if I have to retrieve it the I'll take bin bags to plough through their mess to get to my stuff and their stuff goes out - the bags will be next to the bin if they don't sort it the binman can have it...
No chores done = no pocket money/extras
Who pays for their phones to access data? Withdraw that privilige - stick them on pay as you go - no chores - no payment
Go on strike - don't do their washing, if it's their mess - chuck on their bed and close the door.