It can vary widely (see the active thread on this board about strange travel policies). There's no one standard out there...some firms are looser about booking business class flights on long-haul trips, some do flat per diems instead of receipts, some have tight negotiations with specific hotel chains, etc.

For a gig where you're on the road 55% of the time, especially international, it's completely fair game to simply ask the headhunter to get a copy of company's actual travel policies. If you are looking for an answer to a specific question that isn't in the policy, just ask it.

The only caveat is that with most firms, you'll probably have an easier time negotiating your starting salary than negotiating a permanent exception to their policy. In other words, if the travel policy stinks but the gig still sounds cool, I'd just build that information into your salary/bonus request as opposed to trying to become the only sales guy in the entire firm allowed to fly biz, stay in unusually luxurious hotels, or have unlimited meal expenses. The hiring manager probably can't cut that kind of deal anyway at a large firm.