How safe it is to let ah beng repair my phone?

i brought my hp for repair and the ah beng asked for my hp password which i refused to give. but somehow i feel that they can still access it, please correct me if i'm wrong. is it really safe to let hp shop folks repair our phone, is there any protection at all? i mean they can dive straight into your phone data, photos, etc..

therebis always risk involved yeah. better to bring it back to manufacturer. else just pwd protect ur phone.