Beaujon was proved innocent of any wrongdoing in a court of law (though to be fair he had made a tidy sum saving his city) but finding the scope of the provinces too restrictive for someone of his talents and ambitions anyway, he removed to Paris where he was to remain until the end of his days.

(Some later writers would assert that he fled Bordeaux due to unpopularity following his "profiteering" in connection with the famine, but Masson shows that this was clearly not true, being more probably a case of the sort of calumny the extremely rich always seem to attract.)

In 1773, he bought, for the price of one million livres fixed by the Abbé de Terray, the Hôtel d'Évreux in Paris (today known as the Élysée Palace, the official residence of the President of France).

In addition to his city palace, Beaujon also commissioned the architect Girardin to create a "folie" for him on the considerable land attached to his principal residence (it extended in a wide band running to the north of the Champs-Élysées all the way to the modern Arc de Triomphe).

This pleasure palace was built in an exotic style with a large central pavilion anchoring four attached apartments wherein he lodged his four mistresses of the day who, it was said, more than tolerated each other, inviting each other to dine and socialize in their suites with or without their patron.

Their children were to have no heirs of their own and so even the illegitimate line of Beaujon was ultimately extinguished, though as a last gasp, the brief marriage of Alphonse's son Edouard to the famous "Lady of the Camelias" (the inspiration for both "Camille" and "La Traviata" does lend a final bit of glamour to this genealogy.

Beaujon died in Paris in late 1786 of a hemiplegia (semiparalysis probably brought on by a stroke) and was honoured with a huge funeral pomp culminating with the deposition of his remains in a magnificent tomb in the chapel of St. Nicholas of Roule, which had been founded by him and built by his architect Girardin.