Is it permissible, according to Sharia, to dissolve the private endowment consisting of the three villas? Is it permissible for the questioner to benefit from their price? Is it permissible for him to rent them out so that their revenue may benefit the beneficiaries?

It is impermissible to dissolve an endowment (waqf), sell it, or dispose of it in a way that removes it from its endowed status as long as its benefits remain. Therefore, it is impermissible to sell the endowed villas or their price. However, those for whom it was endowed may rent them out and benefit from their rental income, unless there was a condition from the endower that prohibits this.