This may not be it but I was reminded of Alexei Pansin's Villiers' books:
The three Villiers books (not technically a trilogy, but rather the first three books of a projected longer series; sadly, the fourth book in the series has been pending for thirty years now) are:
Star Well (1968)
The Thurb Revolution (1968)
Masque World (1969)
They concern an impoverished but dashing young man, Anthony Villiers by name, who wanders the interstellar Nashuite Empire in the company of a woolly, toadlike humanoid alien named Torve. Villiers, it develops, is a remittance man: he doesn't get along with his family, so he is "requested to travel . . . and is provided with a reasonable amount of money [sent to him in installments as he travels] as long as he stays away from home." (Star Well, ch. 5) Unfortunately, the remittance doesn't always arrive at the expected place and time. The result is that Villiers can move in the highest of high society but never has quite enough cash on hand.
Over the course of the three books there are duels, and assassins, and bureaucrats, and syrupy children's-book authors, and incisive narratorial comments, and wry irony and wit, and laugh-out-loud funny bits. The whole series, especially the second book, is charming and highly recommended, especially at this price, especially given that the series is long since out of print and probably difficult to find anywhere else. (Though you can occasionally find copies of Star Well or Masque World at used bookstores.)