Christina El Moussa is just as good at flipping men as she is houses ... or something. Looks like she and Tarek are seeing other people, alright.

She's reportedly dating Gary Anderson ... who was also there when now-estranged husband Tarek left the couple's house with a gun in May.

Gary not only witnessed the incident and was on the scene when police responded to a "a call of a possibly suicidal male with a gun."

He's a contractor who works for the HGTV Flip or Flop couple!

Anderson is the one who told police he saw Tarek bolt from the house and onto a hiking trail, prompting the Christina El Moussa 911 call.

Gary claimed Christina, who was shaking and crying, told him Tarek had taken a gun (which he later said was just for protection from wildlife).

While he's done work for the El Moussas, Anderson was at their neighbor's house when Tarek bolted, according to police quoted by TMZ.

Fast forward a few months and she was ready to hit the market!