I would like to hire a Manufacturing Expert

I am starting a company that sells t-shirt 'sweaters'. Mainly for 'bigger guys' with the desire to wear a sweater but without the sleeves. Sweaters can be hard to fit when arms are involved, they are either too short, too tight, not often too long. I'm trying to find a company that can produce my product and design for cheaper and quicker than I can do myself. I'm not selling regular t-shirts here though, it's knitted sweater t-shirt style. Looking for a v-neck style, regular fit style, round/crew neck fit style, and lastly a design where there is a few buttons to undo at the collar, but still pulls over your head... I need these produced somehow for an affordable price, good quality, consistent and reliable. This task could be completed in more than one way. The designs could be made for a sample and sent to myself, and/OR help me find a manufacturing connection that meets my above needs.