To be honest the Hilton BRG is hardly worth the effort and frustration for just 25% off a rate (usually) just a little below Hilton's own. Of course, there are exceptions - and longer stays can bring significant rewards for the effort.

IHG's scheme used to focus minds with a free night if you found a lower rate: great for one night stays! There the drill that worked for me (and IHG) was comparing the hotel rate complete with taxes, to any outside net rate that included taxes: it seems a sensible approach, comparing final bills.

It got more difficult to win the BRG as it became better known and more widely understood, and was ditched last year for something feeble resembling Hilton's scheme.