Possible problems: mold, fire from using lots of power and funky cords unattended, bugs (white flies, gnats, mealy bugs etc), attracts mice, high water use and high electric use alerts utility and police, the neighbors can smell it and attracts break ins and theft, bad guys, and so forth.Don't know what your lease says or how you feel about the risk but if there are twenty plants you are responsible, you can lose the property if there was a fire or a raid.