Our renewals/memberships exist as open opportunities within Salesforce. We would like to match incoming payments with these expected pledges on import. However, requested amounts, expected close date, and other payment information varies from what is ultimately received. The only item that can really be matched on consistently is Record Type ID and the Contact. Everything else can be different from the file to the opportunity in Salesforce.
Example: John Smith pledges to pay $100 on 6/1/2021 - this is recorded in SF with a 'Solicitation' stage. We receive a file from Fidelity which includes John's payment on this pledge, however, he has paid $200 on 5/15/2021. The open opportunity for John Smith should be updated to include the new amount, and close date, and to update the Stage to Closed Won.
In some cases, a contact may have multiple open opportunities, and we might need to choose which of those opportunities is the correct match.