A large photo booth company needs to be in front of all the prices. Large companies provide all-inclusive rates which means no surprises. When you compare the price between the two companies is important that you know what the price includes. You can find mobile photo booth services from various web sources.
That being said there are some things that you should not be charged for, and if someone does not charge for this I would classify this as a company to avoid.
There are two things that make a great photo booth companies. # 1 is their customer service and # 2 is the quality of their booth.
They can be the best people on earth but if it looks cheap and flimsy booth drastically will take away from your guest experience. Also, the booth can look really nice but if you take a bad picture and it takes minutes to print your picture your guests will get bored waiting and not many of them will get a chance to enter the booth to have a great time.
A large company will have all the latest technology. One thing you really have to ask about what kind of printer usage of the company. The laminating dye-sub printer is the industry standard for quality. These printers can produce prints in seconds that is synonymous with the quality of what you would get from a professional photo lab. These photos are waterproof and should last for years.