Only if the Montana plant's schedule genuinely depends on a decision date. Premium processing buys a faster response window under the fee schedule; it does not improve the chance of approval, and a request for evidence resets the clock. Spend the money on evidence quality first.
Buy time only after the file is complete
The government charges for an L-1B petition are the I-129 fee and applicable supplemental fees set out in the USCIS fee schedule, plus the optional premium-processing fee. Hypothetical example: a Lake Country panel manufacturer has a Montana builder waiting for its first panel run and wants the planner on site within weeks; premium processing can shorten the wait for a decision, but if the specialized-knowledge evidence is thin the likely outcome is a request for further evidence, which pauses the premium clock and delays the plant anyway. The company should therefore invest first in documenting the process, the affiliate relationship and the planner's history, then decide on premium processing based on how much slack the Montana schedule has.
Professional fees are separate. Consular visa fees apply if the planner needs a visa stamp, though a Canadian citizen may apply for admission with the approved petition at a port of entry. Keep a record of who paid each charge.