Is it permissible to partner with a contractor who constructs unauthorized floors and pays a "tip" to officials, then reconciles with the municipality, given that I cannot undertake the project alone?

If the authority responsible for regulating construction specifies a limit that may not be exceeded for the benefit and safety of citizens, then circumventing it is considered treachery, deception, and is forbidden, based on the Almighty's saying: "O you who have believed, do not betray Allah and the Messenger or betray your trusts while you know [the consequence]," and the saying of the Prophet, peace be upon him: "He who deceives us is not of us." If money is paid for this purpose, the payer is a briber and the receiver is bribed, and the Messenger of Allah, peace be upon him, cursed the briber, the bribed, and the intermediary. However, if the prohibition against extending buildings is not intended for the public good, but rather is a means of unlawfully seizing money, then there is no objection to circumventing it to obtain one's right, although the first possibility is more likely.