One of the world's first set of travel photographs is up for auction and it's expected to fetch up to $20,000 (£15,096). The images — which are widely considered to mark the birth of travel ...

A recent World Travel Market global report spoke of a wave of consumer demand for 'pay what you want' pricing, 'core free goods' and auctions - it almost sounds like a revolutionary cry.

"The great thing about an auction is that it allows you to determine whether that upgrade is worthwhile for you," says Scott Mackenzie, creator of the travel advice blog Travel Codex. For example ...