Personally, I think that "economical" is one of those "in the eye of the beholder" sort of things when it comes to what you're talking about. If you're looking for a material that will be durable, easy to install, and not require a great deal of maintenance/repair in the future, I would go with fiber cement siding myself (i.e., Hardi Plank). We just finished residing our home ourselves and went with that option purely for the longevity of the product. Vinyl is nice from a maintenance standpoint as well, as you won't have the painting and upkeep, but the initial installation might be more than you want to deal with. Also, if you're like us (we have a detached garage that we wanted to have a similar appearance to the main living space) we went with the lap fiber cement for a sense of continuity. I did a lot of research before deciding on what to go with, and we found that the fiber cement siding products that are out there are not much more than the other materials, can often be found on sale if you check the Sunday adds for the big box stores, and are value added if you ever want to sell the property.
One thing with the fiber cement, however, is that to properly install it, you might want to consider buying/renting a pneumatic nailer for the installation. If you go this route, make sure you are intimately familiar with the manufacturer's installation instructions. Don't use a framing nailer to install this type of product! Also stay away from hardboard siding. While it's a bit cheaper up front, it really does require a bit more maintenance. Our garage is only three years old and the previous owner installed hardboard (Masonite-type) siding that had already gone bad due to inadequate preparation and painting. Just my $0.02. Good Luck!