More complicated than buying a used car, but not horrible. The biggest issue is getting seller alignment.
On the cash front, ferry flights to the US are the biggest expense by far. A 777 burns ~$10,000 in fuel per hour, so positioning from (say) Asia to a boneyard in California adds up quickly... with crew, ferry insurance, landing fees & sundries you end up at $200-$250k. Parking runs around $3-5k per month in the desert, too.