I live in the Negril area, but I don't live in or near Tank Hill.
I can't tell you what it's actually like to live up there, but the Tank Hill area has had its issues in the recent past.
If you're willing to spend up to $900us for a month...I would phone/email a few hotel properties and ask them for long term rates. Most of these properties will have everything you require plus the bonus of security on the property.