Re: Signing with multiple companies....
As you are new, you probably don't realize that posting the same question in two [or more places] is confusing, as it splits the replies & makes it hard to follow.
As this is the proper forum for the question, I'll say that it can be done, but is a headache. Most carriers expect you to be available, [the name brands, at least], and will begin dispatching around you if you often aren't. There's also the question of authority and insurance - if you don't have your own, you will need to make sure you're covered under someone's, and don't even think about running for Carrier A with Carrier B's signs on your vehicle....
Some of our members do it, but [especially for a newbie] it takes a good bit of knowledge & juggling to manage.