Source Pre-owned Test Instruments USA

I am looking for a U.S.–based partner who can track down reliable, fairly-priced, second-hand test and measurement instruments from both Rohde & Schwarz and Keysight. Price is the primary driver, provided the units remain in good working order... (Budget: $250 - $750 USD, Jobs: Inventory Management, Market Analysis, Market Research, Procurement, Product Sourcing, Sales, Sourcing, Supply Chain)