Leviticus 27:11

But if he is poorer than your valuation, then he shall be set before the priest, and the priest shall assign a value to him. The priest shall assign a value according to his ability to pay.

“‘If it is an animal of which men offer an offering to the LORD, all that any man gives of such to the LORD becomes holy.

He shall not alter it, nor exchange it, a good for a bad, or a bad for a good. If he shall at all exchange animal for animal, then both it and that for which it is exchanged shall be holy.

and the priest shall evaluate it, whether it is good or bad. As the priest evaluates it, so it shall be.

But if he will indeed redeem it, then he shall add the fifth part of it to its valuation.

“‘When a man dedicates his house to be holy to the LORD, then the priest shall evaluate it, whether it is good or bad. As the priest evaluates it, so it shall stand.