Income from house property

 As per the I-T Act, if an assessee owns more than one house, then one house of his choice is considered as self-occupied & the remaining house(s) are considered as deemed to be let out. 

However in your case you are already lettin-out your property on rent. so that would be considered your let-out property.  The other house in which your parents are staying, that will be a self-occupied property.

in case of your leto-out property, you will be able to get deduction of Municipal taxes paid from your rent received during the year.  On the balance you will get an standard ded of 30% for the expenses incurred.  this deduction is of fixed amount, whether you incure any expenses or no.  If there is loan going on on this property, then the interest paid on this would be deductioble from the rent paid.

in case of your self-occupied property, if there is any loan going on, then you will get the deduction of interest paid from your total income.

apart from teh above, you will also be eligible towards exemption from HRA, provided that you are paying rent.

As per IT act, one cannot claim both HRA and Loss from Self-occupied property. Eventhough your parents are staying at one of the property you have, you have to claim that as "deemed to be let-out" and not self-occupied.

There should not be overlap between Self-occupied and HRA exemption.

i have only one house in chennai which has been let out and I am staying in a smaller house paying lesser rent.What is the treatment of house rent received and also paid

House Rent recd would be added in your taxable income subject to the deductions towards municipal tax & std ded.  For house rent paid you would get exemption in respect of HRA received to the extent specified u/s 10(13A)

House Rent recd would be added in your taxable income subject to the deductions towards municipal tax & std ded.  For house rent paid you would get exemption in respect of HRA received to the extent specified u/s 10(13A)