Need to recover 6l from a fraud builder

Hello, Dear Sir/Madam My dad has committed a foolish mistake & has lost 6L in total as on date without any property being handed over. The builder like always has played a scam by showing properties in various areas & kept him interested & he went on investing in parts & has also been given some property papers, receipts Now the situation of my father is financially turned weak & has bearly few money in his hands & he keeps me asking for money while he has lost most in this foolish deal & now neither is taking any action to recover this money instead has paid more which is purely foolish despite all this he hasn't reached any single legal option yet & I am fed up of this stupid trouble that's been going on. Honestly, since the start I was the one who said no to this scheme yet he invested, I have work in the social field under political org for people & as you may all know people in social work mostly make the bare minimum enough to make break-even but due to this issue I am being personally being pushed to contribute while I can deploy muscle power but logically I don't see any sense in that apart from the builder going to the hospital plus it may attract another liability which I don't want to get into. I do know there are many legal ways to get money back. Hence I would be interested to get my dad's money back from this idiot builder so I can continue with my social work for the people without dealing with the daily distress going on in the family related to this foolishness. Please, let me know a way out of this