Executor worries

Don’t no whether I should be on here but any advice would be great.
Bassically executor also a beneficiary wanted to buy the property in a will. He wrote to all other beneficiaries with letter of intent to what he wanted to do.
Our reply was to get 3 valuations to get fair market price.
Executor refused and said he can do as he wants.
He moved in at our anger and no agreements
We recieved some cheques but not for value of the property.
He live in property for 33 months without full payment of any agreed price.
Executor puts up for sale and sold at an estimated profit of approx 80k.
Now moved out with new purchaser in property.
Executor ignoring all communication
What I would like to know is he liable for rent to the estate and would the profit be part of the estate.
Would this be classed as self dealing. And what can we do. Surely this is fraud as he’s missing.
Any advice would be great.