Effect of power of attorney

There are 3 types of transfers:

1) Sale

2) Gift

3) Inheritance

I think you can only add your mom's name into the ownership of the flat as second holder. 

In my opinion it is gift. but i want to know the tax effect of such transfer.

can any one help me????

Before preparing a gift deed, you will have to seek permission from the bank who has given housing loan on that flat.