The similarities would be that both are concerned with quality, price, warranties, and the performance of the product.
Differences would be more dependent on the individuals and organizations. For instance, organization buyers might need quantities in timeframes that present delivery problems for their preferred vendor, so they are forced to buy from another. They are also concerned with both public and management perceptions. This would be evidenced in police departments always buying domestic vehicles or the old saying "no one ever got fired for buying IBM".
On the other hand, individuals may well buy with an eye to cache and status that organziations would be unable to justify in the boardroom. Overall, and this is a broad generalization, the individual often purchases from an emotional place and the organization buys from a more rational one.