Christine Quinn 's "Selling Sunset" comeback has hit a snag ... and it all comes down to location and accommodations ... TMZ has learned. Sources with direct knowledge tell TMZ ... Christine is still in active negotiations to return for Season 10, but the deal hasn't been finalized as both sides remain stuck on logistics tied to where she'll live during filming, and who's footing the bill. We're told the main issue is that Christine currently lives full-time in the Dallas area with her son,