Scott Disick Tours $115M Mansion with Girlfriend Amelia Hamlin

Scott Disick's in the market for some very expensive homes ... and he dragged his girlfriend along for what could turn out to be a family real estate investment.

Our sources tell us Disick and his new GF, 19-year-old Amelia Hamlin, went and toured a massive estate in L.A. last week ... the place comes with a whopping $115 million price tag.

Here's what that kinda price tag gets you at the Owlwood Estate ... 9 bedrooms and 12,201-square-feet on a 10-acre plot in Holmby Hills. The place is decked out with a library, sunroom, full tennis court, Olympic size pool and a pool house ... and its former residents include Tony Curtis, plus Sonny and Cher. Daily Mail first reported the pair's extravagant house hunt.

We're also told Scott and Amelia -- daughter of Lisa Rinna and Harry Hamlin -- checked out a $65 million home, also in Holmby Hills, which boasts 9 bedrooms and 30,000-square-feet of pure luxury. Agent Tomer Fridman showed them the property.

The $65 mil mansion looks like an art gallery ... and it also comes with a 3-story guesthouse, cinema, outdoor ballroom and an entertainment complex.

Again, Scott may not be looking to buy on his own ... it's possible some of his family members might want in on a property too, if they determine it's a good investment.