Hra - rent agreement

rent receipt is sufficient ya but you actually transfer the amount to your mother account and your mother shows the exact anount of rent received as income from house property so that at the time of your assessment you don't get trouble.

Rental agreement is not necessary

 YOUR COMPANY  may  Ask PAN CARD COPY OF YOUR OWNER

See subclause 9 in clause 5.3

in circular 8/2012, dated 5/10/2012

You can confirm with following circular

https://law.incometaxindia.gov.in/DIT/File_opener.aspx?page=CIR&schT=&csId=b6b49d91-602b-44e0-a5e2-b6edf7373fbd&crn=&yr=ALL&sch=&title=Taxmann%20-%20Direct%20Tax%20Laws

Agreement is not required  to be obtained, only Rent Reciept is sufficent.The employer may ask to give PAN of  Landlord if the Rental  amount exceeds Rs.1.8 Lacs(p.a). Further, the one is not require to submit rent reciept if Rent is below Rs3000/- P.M

Only rent receipt is suffient. rent agreement is not valid for HRA Claim. & your mother have shown in Income from House  Property  & Excess Rent paid Rs.  15000.00  P.M  required Landlord PAN No.. 

Thanks

Regards

Ramanuj