Chase payment of outstanding invoices

Your action is to chase payment of outstanding invoices by a direct telephone call and e-mail
I will provide copies of the invoices and email correspondence.
I will provide the coordinates of the client
You will provide a feed back in case of need in the future: relevant person tel/mail
You will ensure the payment will be really settled

2 customers with 5 outstanding invoices in 2015

We would appreciate a fixed price