legal advice on buying a property?

we r planning to buy a semi-independent house from a real estate builder.
the case is
1. the owner of the land has given “power of attorney ” to the builder and has not sold the land to builder.
2. we do not know if the owner of the land is alive or not and we r trying to contact her.
3. builder says he will produce latest( date if which is unknown) power of attorney documents.

my doubt is :
in this case can i proceed to buy the house? in future can the owner’s children file a case against this property and claim it to be theirs as the owner has not sold to the property but only given “power of attorney ” to the builder?
also the owner will not be present during registration, it will be the builder who will sign when we register the property.

My mom is 75, a mental patient. her tenants stopped paying rent. ideas other than legal r welcome?

My mom is a senior citizen and had rented her property in Madurai to a reputed organisation. Two years ago, due to health reasons, she moved to stay with me in Mumbai. Immediately her tenants stopped paying rent. Despite repeated attempts, they neither pay rent nor are ready to return the property back, what to do other than legal procedure-which is very time consuming apart from being expensive. Please give good suggestions to deal with this problem.

Legal property issue. My mother in law’s’s father died without passing on the property to anyone.?

So legally my mother-in-law and her brother owns the property. Now, if my mother-in-law does not give the property rights to her brother and dies before that, then the property will be transferred to my husband. My question is, will I or my daughter have any right in the same? Can my mother-in-law’s brother pass it on or sell it without our consent? To sell it off, who’s signature is required?

This is urgent and very important. pls help