Gst query

Sir

1 QUERY

1. I am doing  a properitory businees under GST

   I have let out my personal property to individuals and commercial purpose and receiving rent:-

    a. Now under GST Act will this rental receipts will be clubbed with my business income

    b. If so ,am I have to collect GST from my tenants

    c. Is there any limit for rental receipts for levying GST to my tenants.

2. QUERY

 I am manufacturing Asbestos cement pipes.As per GST Act Cement pipes attract GST @ 18% ,But while manufacturing the cement pipes,I am using cement whose GST is 28% .In this case am I have to collect 18% or 28% for my product Asbestos cement pipes. 

Awaiting for your reply

Thank you

Sunil