DSA Income and Expenses allowed

If an Assessee is receiving 10 lacs as DSA income (income from commission), TDS is deducted u/s 194H,

Assessee's Clients had paid Stamp duty of Rs 4 Lacs for Home loan & and Assessee agrees to reimburse the said Stamp Duty to its client

So, Assessee is reimbursing the Client (who has taken home loan) the stamp duty expense of Rs 4 lacs.

1. Can the Assessee claim salaries, rent and other business running expense? 

2. Can the Assessee claim this Rs 4 lacs as business expense?

3. Which ITR should be used to file return?

4. Can return be filled using Presumptive Income from business (44AD)?