Applicability of accounting standards

why is there such a huge diff.  What does teh reimbursement consists of?

In CHA service, the cha takes money from their clients & incurrs expenses such as shipping charges on behalf of them, & for that service it charges some small fees

But at time of reimbursement sometimes they take even reimbursement of those expenses which are not incurred

then how does the re-imburser re-imbruses the expenses without production of bills.

moreover if they take charge huge amounts then thye would be definitely liable to pay ST on these amounts.

Simply by giving same biils to many parties & it pays te ST to govt on excess amt recd. But what wiil be turnover for AS applicability