Onyx Investment, L.L.C. 3830 N. Maney Oklahoma City, OK 00007-3112 Onyx Investment, L.L.C. Onyx Investment, L.L.C. is an Oklahoma collection agency. Oklahoma collection agencies can help businesses, medical practices and facilities that are creditors to collect their accounts receivable. Debt collection help might include; collection demand letters, debt collector phone calls, … [Read more...]