1. IF Husband demises, THEN you will need to revoke the "joint" POA. IF POA is not joint, THEN Husband's POA will legally lapse, on his demise.
2. OPTION: Both of you Revoke the current POA, and execute afresh another POA, with strategic clauses, with limited purposes and limited time frame and limited conditions and limited rights to receive and give you the sale proceeds. POA is a matter of strategic clauses.
ALSO CONSIDER THIS:
1. ONLY a proper Stamp Duty paid (500/-) and Registered POA holder is entitled to execute any immovable property transaction before the local registrar of sub-assurances. IF the POA is not registered, THEN the whole proceedings shall remain illegal. POA can be given to ANYBODY, irrespective of relationships.
2. POA may have strategic clauses and time limitations of the deal (payment terms, validity time period of the POA document ....), for safety of the POA giver.
3. POA can be registered anywhere in India, before the local registrar of sub-assurances and shall be valid throughout India. Stamp Duty on POA is not the same as Stamp Duty paid on Sale /Purchase Deed.
4. POA document can be endorsed abroad by the local consulate office and SUBSEQUENTLY stamp duty paid and registered in India, for it to be legally enforceable.