GSA has a list of "approved" vendors for services and maintenance for vehicles. A common example of inflated cost would be a local prime vendor charges, lets say, $150 for a new tire, balance, rotation, and installation on a GSA "owned" vehicle. If I have to replace that tire, I am limited to this (or similar vendors). The problem is, I can ge the same tire (EXACT SAME TIRE) at Walmart, Goodyear, Pep Boys, and several others for 65$, plus a warranty(that is still good for government or corporate customers) for road hazards.
Besides the blantant savings in tax dollars, the GSA Vendor purchase must be repeated when I blow out a tire from a broken bottle on the road for a loss of another $150...the Walmart/Goodyear/Pep Boys tire gets REPLACED (within the warranty period) for nothing but the $2.50 tire disposal fee.