Exclusive Luigi Mangione Flexed Wealth on Vacation Before CEO Shooting … $6 Million From Fam!!!

Luigi Mangione mentioned the big bucks he had in the bank on a trip to Thailand … and also, repeatedly brought up a couple of revealing books — TMZ has learned.

A source — who doesn’t want to be identified by name, but who spent significant time with Luigi back in April — tells TMZ … the two went to the popular tourism destination together, hitting up bars and visiting a weed shop, and cracking inside jokes over a period of two days.

According to his friend, Luigi was “making lawyer money” coding for TrueCar … a telling statement because Mangione reportedly stopped working for them months before going to Thailand.

He told our source he had $6 million in the bank, all of it coming from his family. Talking about his family seemed to be a sore subject, according to the friend, so he didn’t press Luigi on it.

Our source says Mangione might have mentioned owning a 3-D printer too — remember, it’s been reported police believe the gun he allegedly had in his possession when he was arrested was 3-D printed.

Our source says Luigi mentioned 2 books repeatedly during their days together — “The Secret Assassin” by Joseph Conrad and “Confessions of an Economic Hitman” by John Perkins.

The former is a well-known classic in English literature … focused on a character who commits a bombing to convince the British government to quash Anarchist leanings before he himself is fatally stabbed.

The latter book is a semi-autobiographical book published by Perkins about his time working for the engineering consulting firm Chas. T.

Main … which claims he went to underdeveloped countries with loans to build infrastructure — which helped essentially trap those who took the loans into a system of American control.

Our source says he also read Perkins’ book … and, the two discussed it in detail — talking about how they both enjoyed takeaways from it.

Luigi and our source last spoke in July … when we’re told Luigi blasted the U.S. healthcare system and talked about the need for universal healthcare.

We’re told he talked about needing change in general — and didn’t specifically point to any health issue he was having — including the back injury that’s been a topic of discussion.

We’re told he only brought up his back once on the trip — saying he was hopeful that hot springs in Japan would feel soothing.

As you know … Luigi was charged with first-degree murder in the killing of UnitedHealthcare CEO Brian Thompson earlier this week. He’s still fighting extradition to New York City from Pennsylvania.