I would create a view that consists of a union query of the fields you need from AROBP & OEPPRE with just the fields you need with matching aliases. something like:
SELECT IDCUST AS Cust, IDINVC AS Doc, IDRMIT AS [Check], DATEBUS AS PayDate, AMTPAYMHC AS Amount
FROM dbo.AROBP
UNION
SELECT dbo.OEORDH.CUSTOMER AS Cust, dbo.OEPPRE.DOCNUMBER AS Doc, dbo.OEPPRE.CHECKNUM AS [Check], dbo.OEPPRE.CHECKDATE AS PayDate, dbo.OEPPRE.PAYMENT AS Amount
FROM dbo.OEPPRE INNER JOIN
dbo.OEORDH ON dbo.OEPPRE.DOCNUMBER = dbo.OEORDH.ORDNUMBER
WHERE (dbo.OEPPRE.APPLYTO = 4) -- for orders
With more UNIONS for shipments starting with OEPPRE but using the appropriate tables instead of OEORDH