Thanks you reply.
I got my rattle problem fixed. I went to Plaza Crash Repairs in Holden Hill, Adelaide 5088. The guy (Eric Giro) of Plaza Crash was very honest and knows his stuff; He slightly opened the roof liner near to the rear side air bag and found a loose spring sort of thing and put a piece of cardboard between the spring and roof and it all gone! Eric spent about 45 mins and charged nothing! That's a great favour ( CMI Toyota Quoted $1500 for this)
I am very impressed with Eric and his family owned business with very clean nice yard. I highly recommend to have a look at Plaza Crash Repair (Plaza Crash Repairs and Towing Service | Holden Hill | Adelaide
) and talk to Eric for any crash related stuff/advice/quote.