A business line of credit functions like a corporate credit card with a higher limit: you're approved for a maximum amount, draw funds as cash flow demands, pay interest only on what you use, and the credit replenishes as you pay it down. Watertown retailers near the Arsenal Yards development and service contractors working Belmont Hill estates rely on lines of credit to bridge invoice delays and weather the slow winter months without exhausting cash reserves. Timberfield Financial, a licensed commercial-loan broker at 1 Broadway, Cambridge, MA 02142, (617) 545-7807, matches Watertown businesses to lenders offering unsecured and secured lines, typically funding within five to ten business days once documentation is complete.