Painting - Exterior Painting

I'm currently in the process of getting quotes to paint the exterior of my home. Here are my questions.

1. I have a 2 story home and the bottom portion is stucco. Is 2 coats of Benjamin Moore paint good enough? Would it be better sprayed or with a roller? Would one coat primer and one coat paint be good enough?

2. Second level is aluminum siding. Would it be okay to apply paint with roller? Should I have them spray it instead? Would 2 coats of paint be better than 1 coat of primer and one coat of paint. I have received different opinions from different painters.

Thanks in advance for your help and suggestions.

Between your choices, I would go for the 1 coat primer, 1 coat finish. But if the color is changing, or there is any apparent problems, I do 1 coat primer, 2 coats finish. If its all in great shape, and color won't be changing, 2 coats finish would be fine. Did I confuse you anymore?:D

I prefer brush and roll over spraying.

Why are you painting aluminum siding? I thought siding was to be maintenance free?

Thanks for the response. Stucco color right now is natural or it's original color which almost looks like a primer. We were going to do new but decided to just paint since it's not in bad shape.

In regards to the siding, out here in the northeast, a lot of people do have the siding painted versus replacing. Siding used to be a very light green but almost looks white since it seems like the original and house is 50+ years old. Actually the quote I received for brushing and rolling is cheaper than spray.