Second this. Landlords don’t want their stuff screwed up by inexperienced tenants’ diy projects, and they don’t want to pay for something they think it’s unnecessary. I’d get an estimate for a pro to do it (could be a guy off Craigslist or whatever, just someone who does this for a living) and then just ask the landlord if they’d be alright with you paying to get it done. They’ll probably want to know exactly what they’re going to do, and they’ll likely say yes, especially since you say they already have coax running through the house.