Laptop exchange offer accounting

https://www.caclubindia.com/forum/a-c-entry-for-exchange-purchase-of-fixed-asset--150334.asp?offset=2

I don't know why it's like that. It's must be an example under variable consideration. There are no examples so let's make up one. You sell new laptop for old one.

New lappy 500. Old one 100.

So

Dr. Bank 400

Dr. Inventory 100

Cr. Sale 500

Usually it's inventory, but if the company has a plan of using them in their own plant, it can be treated as fixed asset otherwise inventory. 

When a laptop worth Rs. 100,000 is exchanged for an old laptop with a value of Rs. 90,000, the accounting treatment and journal entry would depend on the method of accounting used by the firm. There are two methods of accounting that can be used in this situation: gross method and net method.

Gross Method:
Under the gross method, the exchange is recorded at the gross amount of the new laptop. The old laptop is treated as a part of the payment for the new laptop, and the difference is recognized as a gain or loss.
The journal entry for the exchange of laptops under the gross method would be:

New Laptop Account Dr. 100,000
Old Laptop Account Dr. 10,000
To Vendor Account Cr. 90,000

In this case, the old laptop is not treated as a purchase in the books of the firm.

Net Method:
Under the net method, the exchange is recorded at the net amount of the new laptop after deducting the trade-in value of the old laptop. In this case, the old laptop is treated as a purchase in the books of the firm.
The journal entry for the exchange of laptops under the net method would be:

New Laptop Account Dr. 90,000
To Vendor Account Cr. 90,000

Old Laptop Account Dr. 10,000
To New Laptop Account Cr. 10,000

In this case, the old laptop is treated as a purchase in the books of the firm, and its value is recorded separately as an asset.