Hello,
When You are selling through snap deal , I think ,the buyer would be someone else than snapdeal. So in my openion, When a sale is happening, You should make the following entry.
Customer A/c .....Dr 500
To sales A/c 500
When sale consideration is received from snap deal.
Bank A/c ..............Dr 400.00
To Snap deal A/c 400.00
( Amount transferred by snap deal on behalf of customer)
As per snapdeal FAQ for vendors, it is understood that they are charging commision on sale. Commision normally attract TDS of 5 % with an yearly limit of 15000. But in your case it is 500, hence no need to deduct TDS. Lets make this entry as follows.
Commision Paid--- Dr.......... 100
To,Snap deal A/c ........................ 100
Now lets, adjust the balance amount of customer a/c to snap deal to close , the customer a/c and snap deal account by passing an adjusting journal entry.
Snap Deal a/c ....dr 500.00
To Customer A/c 500.00
( Being amount settled by snap deal on behalf of the customer)
For making sales entries in tally erp please refer this