If you are using Paypal a lot (As I do), you probably have the problems with Paypal as I do: Search
Paypal has search functions but you need to enter the exact name or email address. But often I don't know it!
So if you use GaragePay you can do searches over all records in the database (for me more than 5 years) and enter the search information you have.
I often have customers where I know their domain name. I don't know what name they use for the account, their real name, some alias or the company name. And often people use an extra mailbox for Paypal. so the email address they use for support questions is not the same as for Paypal.
So I enter the name of the domain and find the records I need. I even have some smart folders defined there (like in the Finder) where I have only the payments of a single customer. In sum a cool app! Try it.