Coronavirus is contagious so you should not be in physical contact with the person who is helping out. Keep at least 2m away from them. They should leave or pick up goods or post on the doorstep or porch. Wash your hands in line with government advice and do not ever invite strangers into your home.
If you need to give them money put cash in an envelope or jar and leave it for them to collect. Do not give your bank details, card or PIN to strangers.