Private trucking schools are not associated with any particular trucking company. They are run independently so students upon graduation can choose to go anywhere they would like. The schools range in price generally from $ 2000- $ 5000 and can take anywhere from 3 weeks to 8 weeks to complete for your Class A CDL license. It would take less time and money if you only wanted a Class B but I strongly suggest you avoid going that route. You are not only embarking on a new job, it's a new career.
By only getting your Class B license you are strictly limiting yourself not only with regard to the number of jobs available to you but the amount of money you can make. It only costs a little more money and takes a little bit more time to get your Class A and believe me you will not regret it. Almost anyone I have ever talked to with a Class B had plans for getting their Class A, but I've never talked to anyone that wished they had only gotten their Class B. Nobody. Go for your Class A.
Many of the better private schools will have a wide range of training including several weeks of practice at backing up the truck, classroom coverage of everything from log books to maps and routing to air brakes and vehicle inspection. They will also have several weeks of training out on the local roadways. Make sure they will give you the necessary training to get ALL of your endorsements including hazmat, tankers, doubles and triples, and people (buses). Make sure you get ALL of these. It only requires a very short written test and can also severely limit your job opportunities if you leave them out.
Be sure to ask the school what their policy is if you do not pass the driving portion of the test for your CDL the first time. A reputable school will continue to work with you for a short period of time to allow you the extra practice you need. They can not guarantee you'll pass it, but they will continue to help you for some time.
Also, most good schools have a job placement program. There is a HUGE demand for drivers nationwide and their job placement department will have a long list of companies willing to hire you the day you graduate. You can tell them the type of job you are looking for and they will have several choices for you. Believe me, getting a job coming out of school is very, very easy. But getting the right job for you at the right company will be much more likely if you have some experienced help with good contacts.
Many schools will also offer financial aid. The money you are required to put up front is sometimes a big limiting factor on what type of school you can attend. Offering financial aid can open up your opportunities. Find out how long it will be before you are required to begin making payments after graduation. Most schools will allow you 3-6 months before you start making payments.
The advantage to attending a private truck driving school is that the training is general for the industry, not specific to one company. Therefore it will apply no matter where you choose to work and will not be geared towards any one company's particular equipment or agenda.
The disadvantage is that it may cost you more money up front if you are not eligible for financial aid.