Having used many charter companies before with mixed experiences, I can say with confidence that Stratos has the best service and highest level of professionalism of any of the charter services I have encountered. Most recently, we had an unfortunate last minute cancellation of a charter booked through another service, and Stratos came through at the last minute to find the right plane at the right price for us with under 24 hour notice. I cannot thank them enough for their professionalism as well as their willingness and ability to go above and beyond to find the right charter for us - even as a first time customer.
You will be told how much the hold can take on your chosen aircraft and can upgrade if you feel more space is needed. This will generally be far more than that of a commercial airline. You may also need to upgrade if carrying things like golf clubs and skis. If travelling with a gun, you will need to provide a license and the gun and ammunition must be kept separate. It is then at the captain’s discretion whether it can be on board.