Can I sublet a unit when I have no lease?

[Joycel Portela]

Hi everyone!

I'm currently living in a townhouse which was originally leased to my father in law 10 years ago. He was never asked to sign a lease renewal and now I've been living there 2 years paying the rent while he moved away for work. He just informed me that he doesn't plan to move back and I'm considering to move out as well, but I'm hoping to sublet to make additional income.  However, the owner is not aware that I've been the one paying the rent and living there. Although the original lease does not impede subleasing, I'm afraid if he finds out that my father in law is no longer living there, that the rent will be increased to market value, which is crazy pricey in Miami and would defeat the idea I have to sublet.

I don't know how to go about this!  I'm assuming subleasing is allowed since it's not specified on the original lease, but since I'm not part of that lease I fear being held liable if I were to move someone in and then they refuse to leave or end up not paying the rent, etc. Any guidance on how to go about this would be greatly appreciated.

Thank you in advance!