Enquiry on POA & Transfer rights

I have an under construction disputed property at Chennai in joint name with my wife, even though she has no financial contribution. Currently we are staying in West Bengal & as she does not want to move to Chennai every time for any transaction related to the property & has no objection in me dealing alone with that, she gave me a general power of attorney (At Chennai Registrar office) to deal with everything. Now in the context of Tamil Nadu specific rule if any my questions are: 1. Is General power of attorney need to be validated every time (as I was told) with life certificate or it remains valid until she cancels it. 2. If General POA to be validated every time & being cumbersome job, is it still possible to transfer all transaction rights to me including property registration, sale etc even though the sale agreement remains unchanged in joint name.