In Luigi’s Mansion, Luigi remarks that he prefers the bottom bunk bed when examining a bunk bed in the Twins’ room (top image). However, in Paper Mario, Page 11 of Luigi’s diary, available only upon revisiting Mario’s house after defeating Bowser, contains a passage where Luigi wishes upon a star to be able to sleep in the top bunk bed (bottom image). The reason for this inconsistency is unknown.
Lets assume that the events of Paper Mario happens before Luigi’s Mansion. Luigi tries the top bunk after Paper Mario, but doesn’t like it that much and concludes that he likes the lower bunk better which is what he says in Luigi’s Mansion