Simple rules take an afternoon. These are the jobs where a wrong rate costs money on every order.
Rate card to rule set. Turning written pricing into ShipMagic rules: zones, weight bands, free-shipping thresholds and surcharges, in the right order, plus a check of what checkout shows when no rule matches.
Carrier quotes that match the parcel. Live rates come from your own carrier account, and ShipMagic packs items with a 3D bin-packing step. Box sizes and product dimensions have to be right first, or every quote is off.
Mixed carts. Rate blending merges rates from several rules or profiles into one. Someone has to decide whether a bulky item plus a small accessory pays the higher rate, the sum or a set figure.
Local delivery and pickup windows. Distance rates, in-store pickup, pickup scheduling, cutoff times and blocked dates, each checked against real locations and staff hours.
Checkout rate cleanup. Hiding, renaming and reordering rates by condition, such as blocking PO Boxes for a carrier. For wider checkout work, bring in checkout customization experts.
Rates before checkout. ShipMagic's docs say its API can show rates on custom pages such as cart and product pages. That is development work, a fit for API integration developers.
Where Speedy Squirrel covers it. The developer offers a free setup call and human onboarding support, and Pro+ includes a developer for coded rate logic. One flat rate needs no freelancer.