8:29 PM PT -- A source close to the couple tells TMZ -- Ben, being the good boyfriend he is, was accompanying J Lo on her own hunt for a mega-mansion -- the two aren't ready to shack up together ... at least not yet.
Ben Affleck and Jennifer Lopez like it, and they're about to put a ring on it -- a housekey ring ... because the couple's jumping to the house hunting stage of their reunion!!!
Bennifer 2.0 was out and about Thursday in L.A.'s upscale Holmby Hills neighborhood, and they had a high-end realtor escorting them to check out a few mansions. J Lo and Ben followed in their own vehicle, stealing a few kisses along the route ... perhaps to celebrate finding their dream home.
We know one of the pads they toured is a $65 million, 31,000 square-foot palace with 8 bedrooms and 12 bathrooms. That's tons of room for them and their 5 kids ... who we're sure would love some of its fun features.
The pad's got a freakin' bowling alley!
Our sources say the couple checked out at least 3 mansions during the shopping trip, which comes a little more than 2 months after they grabbed headlines again by hanging out in Montana ... shortly after J Lo's split fromA-Rod.