Buyer cancelling property Deal after Holding deal for 100 day without sale Agreement

In Janu 2024, we agreed to resale our flat to one buyer through a broker. The flat under consideration is self-occupied but is not mutated and neither are the property taxes paid. The home loan on the property is still running. The verbal agreement was that the buyer would pay a sale consideration of 62.75 lakhs with an advance payment of 10%. The seller will clear all liabilities on account of government taxes & Loan on or before the final deed or registry. The possession of the Flat was 90 Days from the Date of the final deed / Registry as we needed to shift to a new house. However, The buyer transferred only 51000/- stating the balance amount would be paid at the time of signing the sale agreement however, he was not reachable for 15 days due to illness. On the 16th day, he demanded our KYC & Property Documents to process the sale deed, which we refused to provide as the sale agreement was supposed to be signed before the sale Deed along with the agreed advance amount   On the 26th day, after regular follow he stated that he was unaware that a sale agreement and a sale deed are two different things.   On the 52nd day, after discussion and coming to a consensus on the clauses of the agreement,  it was mutually decided to sign the agreement after Holi as it is considered an unauspicious period. In the meantime, the buyer was supposed to have the sale agreement ready for signatures.   On the 62nd Day, we came to know that the agreement was still in draft mode   On the 72nd Day – they asked for some more time stating that the agreement was ready but he was awaiting for funds.   on the 91st Day - as there was no sign of agreement from the last 90 days we contacted the broker to look into this & he arranged an updated copy of the agreement, which was completely different from the one we had discussed at the beginning of the deal.   The copy of the Sale Agreement stated that all liabilities were to be paid and cleared before  "EXECUTION OF THIS AGREEMENT"  & "BEFORE SIGNING THIS AGREEMENT"  in place of the Sale Deed / final registry.The changed terms mean we need to clear our Home loan, and property tax & hand over the possession of the flat before signing the sale agreement itself.   We asked them to replace these words with "BEFORE REGISTRY" OR "SALE DEED", which he refused by stating "execution of this agreement" means after registry only." & he wanted to cancel this deal and refund his advance amount or else he will take this matter to court if we don't agree on these words. As this is a self-occupied property that we had to vacate, we had finalized to buy another house property and have committed to the other party. With this backing out of the buyer, it has put me under immense financial stress. Also, we had held the property for more than 100 days with a token amount of mere 51000/- in good faith and had foregone other prospective buyers.   Can anyone suggest whether the buyer is legally eligible & Our Rights