@Tami R. Do you track your inventory?
@Tami R. I love Amazon, my spending last year was in the upper 5-figures. Set yourself up with a business account if you haven't already. That'll allow you to setup sub-accounts that can purchase using your payment methods (and for you to track the spending), request bulk pricing on items, and apply for NET 30 payment terms (this is awesome).
We stock some doorknobs but try to transition all clients to master-key systems. Dual-detectors for sure. Combo lockboxes. Thermostats, thermocouples, the common furnace control board, furnace filters. Toilet internals, wax rings. Office supplies (prices regularly beat quill). The other great thing with amazon is you can setup auto-replenish to send items like paper every x months.
@Tami R. we are working with 9 doors and use the gamut. Mostly the local hardware that gives us 10% discount and a monthly statement. HD because it records our purchases by credit card.
We also use our personal Prime account as well. We spent quite a bit in the last 2 years while renovating. What I love is the fast shipping, consistent stock and ability to download an excel spreadsheet if your purchases. It is my go to for things that are not otherwise in stock locally.