Which is the Cheapest Citizenship by Investment in 2021?

Antigua & Barbuda offers the cheapest citizenship by investment program. It costs USD $ 100,000 for a family of 4.

St. Lucia offers citizenship by investment program. It costs $ 190,000 USD for a family of 4.

Commonwealth of Dominica offers citizenship by investment program. It costs USD $ 200,000 for a family of 4.