Every fresh admission or petition carries a charge of its own, so three short assignments cost more in government fees than one continuous one. Preparing a new scope document each time is the recurring private expense.
Recurring engagements, recurring costs
Hypothetical example: a Hampton consultant plans three separate six-month engagements over two years rather than one continuous assignment, assuming that keeps things simple. Financially it does the opposite, because each request is a fresh application with its own charge and its own preparation. What the government takes differs between requesting admission at the border and having an employer petition, and the published amounts are revised periodically, so both figures should be looked up from the relevant agency before a multi-engagement plan is settled.
The private costs recur too: a new scope document to draft, updated qualification letters, and professional review of each engagement's description. Where the work is genuinely continuous, a single longer engagement is usually cheaper and, because it avoids a pattern of repeat entries, easier to explain.