In my opinion, living arrangements with the opposite sex should only be used as a last resort only, unless of course they're brother and sister!
People talk, and rumors would fly no matter how well intentioned the situation was. Is one's reputation worth risking?
Ecc 10:1 Dead flies cause the ointment of the apothecary to send forth a stinking savour: [so doth] a little folly him that is in reputation for wisdom [and] honour.