Mark Wahlberg‘s got a new neighbor down in his exclusive enclave in South Florida, and the guy’s got some pretty deep pockets … because billionaire Russell Weiner just dropped $19 million for an estate around the corner from Marky Mark … and we’ve got a look inside.

Real estate sources tell TMZ … Russell, the billionaire behind Rockstar Energy drinks, bought a home near Mark in Delray Beach’s Stone Creek Ranch for $18,005,000.

Here’s what $19 million, give or take, gets you in a small neighborhood known locally as “Billionaire’s Row” …. 11,506 square feet with 7 bedrooms and 11 bathrooms nestled up to a manmade lake.

Russell previously spent $35.3 million for Rosie O’Donnell‘s former estate on Star Island in Miami — where Diddy owns a home — but the big selling point for Stone Creek Ranch is privacy and being off the water.

The gated enclave only has 37 compounds, and residents get guarded entrances with round-the-clock armed security. The guards are all ex-cops and ex-military.

Check out the gallery … no wonder billionaires are moving into Stone Creek Ranch.