1. If employee declares other incomes in the declaration form then the employer should consider all income while deducting TDS from the salary income. In case of loss, only loss from house property would be considered and no other loss.
2. No. Even if the employer is aware of the fact that the employee is earning other income which is liable for tax then it is on the will of the employee to declare it or not.
3. No subject to TDS on salary and HP income should be deducted and deposited properly and timely.
4. No
5. No.