Invoice pricing is supposed to the price from the manufacturer to the dealer on a new vehicle. However, many factory to dealer incentives are not reflected on invoice price so it is not a 100% accurate representation of what the dealer "owns" the car for.

Wholesale pricing is more often referred to in the context of pre-owned cars and is an indication of what the car would be valued at in a wholesale transaction (i.e.between dealers or at a dealer only auction). It represents the amount a dealer is usually willing to pay for a car so that they can mark it up and sell at a pre-owned retail price. I haven't heard the term wholesale price used at all when referring to the purchase of a new car.