The GSP is the cheaper dog on both measures: $100–200 a month against $150–300, and $1,800–3,000 in the first year against $2,000–4,000. Cost level 3/5 against 4/5. The gap is mostly food volume and weight-based dosing — a 55 pound dog and a 95 pound dog are charged very differently for parasite prevention, anaesthesia and any long-term medication. Grooming adds to the Malamute side if you use a professional groomer for the seasonal blow-outs, which many owners eventually do.
The shared risks are hip dysplasia, elbow dysplasia, bloat, hypothyroidism and epilepsy — all five appear on both breeds' lists. Both are deep-chested enough that split meals, no heavy exercise around feeding, and knowing your nearest out-of-hours surgery are sensible precautions.
The divergences are worth asking a breeder about directly. The GSP's list adds von Willebrand's disease, an inherited clotting disorder with a DNA test available, along with progressive retinal atrophy, recurrent ear infections and a meaningful cancer incidence. The Malamute's adds zinc-responsive dermatosis — a northern-breed absorption problem that shows as crusting around the face and manageable once diagnosed — plus inherited polyneuropathy, hereditary cataracts and progressive retinal atrophy.
Lifespan favours the Malamute slightly at 10–14 years against 10–12. Ask for hip and elbow scores on both parents of either breed, and for the GSP ask specifically whether von Willebrand's status is known.