3PL - Warehouse Management Software Recommendation

New in this business and my team needs to choose a WMS for 3PL/fulfillment. Spoke with Extensiv (3PL Central) who quoted us over $1,500/mo to use their software, that's too high as a start. What are thoughts around ShipStation, ShipBob, ShipMonk, Etc. ? Our needs are basic, we want to connect/integrate with our client storefronts and receive orders in real time. It'd be great to have a one stop solution with warehouse, inventory, shipping costs management all in one. All advice is welcomed.