Most corporate travel programs allow travelers to add GPS and electronic toll paying technology to their car rentals, though few corporate travel buyers currently negotiate those amenities with vendors, according to a Business Travel News survey of 228 buyers.

The survey showed that just over half of respondents have policies that allow travelers to purchase electronic toll technology with their car rentals. A slightly higher number allow travelers to add GPS technology to their rental.

Three-quarters of the buyers, however, said they were not negotiating either of these add-ons with car rental suppliers. About 20 percent said they negotiate GPS equipment, and slightly less negotiate for the toll technology.

Bob Brindley, vice president of BCD Travel, a consulting division of Advito, told the Business Travel News he expected more buyers to begin looking into those negotiations. "While car rental companies want to unbundle and charge for these things, if you think from the negotiating perspective, you can include them as part of the negotiations," he said. "It's not dissimilar from unlimited mileage being included, or in the same way some companies pre-purchase fuel."

Electronic toll technology can be an aid to buyers, as tolls paid with the corporate card rather than cash provide better data. Buyers, however, should be sure that travelers are not paying for the technology when they end up paying no tolls during their trip, Brindley said.

GPS technology also has become ubiquitous at car rental companies in the past several years. While some handheld mobile devices can duplicate a lot of those capabilities, many travel managers would prefer their travelers use onboard equipment rather than fiddling with their phones while driving, Brindley said.

One of the obstacles in negotiating the add-ons has been that many of them come with outside deals from technology providers, who set the pricing. Brindley said that is becoming less of an issue, however.

"These tools are going to start becoming more standard," Brindley said. "Initially, they're testing market acceptance and it's easier to outsource, but as they become more standard, it makes more sense to add them in."