Dear Jeyaseelan.A,
Travel reimbursement for candidates is usually aligned to the position for which he/she is going to be interviewed. For example, if you are interviewing a candidate for the position of Manager, then they will be entitled to reimbursement of traveling expenditure that a Manager in your company receives.
Regarding joining, as the candidate will become an employee, your Travel Policy will be applicable, and usually, a separate provision is kept for the joining process, which is in line with the Transfer Policy.
Regards,
SC