In the practice company record:
1. F8 Sales: Gupta Agencies, 10 units item A at Rs 1,000 + GST (new ref INV-001).
2. F9 Purchase: Mehta & Sons, 20 units at Rs 600 + GST.
3. F6 Receipt: Rs 5,900 from Gupta Agencies against INV-001.
4. F5 Payment: Rs 10,000 office rent from HDFC Bank.
5. F4 Contra: Rs 20,000 cash deposited into HDFC Bank.
6. F7 Journal: depreciation Rs 2,000.
Then open Day Book and check each entry.