The possessor in bad faith shall reimburse the fruits received and those which the legitimate possessor could have received, and shall have a right only to the expenses mentioned in paragraph 1 of article 546 and in article 443. The expenses incurred in improvements for pure luxury or mere pleasure shall not be refunded to the possessor in bad faith, but he may remove the objects for which such expenses have been incurred, provided that the thing suffers no injury thereby, and that the lawful possessor does not prefer to retain them by paying the value they may have at the time he enters into possession. (445a)