Question regarding poster and cover designs

I had a question regarding distribution in terms of designing the cover for the DVDs and Blu-Rays for my film. When my film is completed, I do want the poster and DVD and Blu-Ray cover to look a certain way. I understand that films - for the most part - have more than one poster and DVD/Blu-Ray design.

I did want my film distributed by film distribution company. I wanted the film to be available on YouTube (pay-per view YouTube so my viewers can pay for it first) but then again I wanted to hire a company like The Design Studio (that's their company name) via Disc Makers to design the movie poster, DVD/Blu-Ray cover the way I wanted it. Will this be a problem for someone who isn't self-distributing their film?
If you're not self distributing, you'll probably be wasting your time and money. If your film gets picked up for distribution, that distributor will have the cover/poster designed how they want it. Probably for the best too; they're going to know more about marketing than you, plus they're going to have more money to throw at the design than you.

Of course, if your design was really good, they may well use it.