Are contracts concluded for investment, which stipulate the right of the official authority to own the premises after their construction at the investor's expense, Islamically valid, and is this authority entitled to seize the premises without compensation?

If you rented a plot of land for construction, and the contract is valid, then the building belongs to you, and the new administration is not permitted to seize it from you, even if the previous administration did not document the contract. However, the new administration is not obliged to renew the contract after its expiry. In such a case, either you agree with them on compensation for the building, or you remove your structure. Jurists have stipulated that the tenant must remove buildings and trees after the lease period ends, unless the landowner chooses to own them at their value. The Hanafis held that the landowner acquires ownership of the building and trees at their value if their removal would harm the land, while the Hanbalis gave the owner the choice between acquiring them at their value, leaving them for their rent, or removing them and guaranteeing any deficiency. As for the Malikis, the owner of the planted trees is compelled to remove them after the period expires, and the landowner may lease the land to him for a future period.