Do Mutation certificate is a sufficient to prove a ownership .
If the property under dispute (between landlord and tenant), then the original property documents in the name of your parents, along with their death certificates and a legal heir ship certificate, as well as a registered released deed in your favor by other legal heirs of your parents and the certificate of revenue records, besides tax receipts, water tax and electricity connection etc on your name shall b proper and substantial documents to prove your title.
I have never issued any rent receipt, they are paying the portion of rent to the corporation as a occupier tax, Even they are not appearing in the court & it is going to be a ex party , Do they again appeal afterward after Ex-party.
In the absence of any rental agreement it may be considered as tenancy month to month basis.
If they are set exparte and an exparte decree is drawn against them, they need not prefer an appeal, they can file a petition before the same court for restoration or setting aside the exparte decree.