2 1/2 yr old cries all the time?

I am a daycare provider and I have had this child for about a year now he has been this way since i got him. He is very cute and very smart but really and defiant. During the day he will just start crying for no reason and is only ok if I hold him, well that doesn't work out to well for me since I have other kids to attend too. Anything I try to do with him is a fight he tells me no all the time and I don't want to! for example the other day he was outside and came in the house and I said do you want to come in? he said NO! so I said ok well lets go play and I got I don't want to! and he threw a fit right there in the door. Another example is at lunch he will eat good for me but when he stops and I ask if he is done he will push the plate away with a huff and when I try to take the plate away he will freak out so I give it back and say ok you want to finish it and he will say no I don't want to and cry we go back and forth like this. This is how my day goes with him, he likes to be held a lot and is the only time other than nap time that he is happy free play only happy for a few minutes and if I try to sit with him to play he just argues and cries. He has good days but more days like this than good. I am at my wits end with him, but I love him to death he can be so sweet. Did I mention he is a red head? Any help to better work with him is appreciated.