If you like to roll around in the mud, you might like the Outex Waterproof Camera Cover.
It features a patented seal design that keeps your camera watertight (up to about 33 feet) and weathersealed from snow, mud, and dust. The accessory is crafted from a special latex compound that makes it flexible and rugged. It also comes with a large circular window at the rear that allows users to preview images and gives a full view of your camera controls.
Besides covers, the company sells a range of optical lenses, viewfinders, and accessories that can be used as a kit with Outex covers.
The Outex could be a good balance between functionality and price considering what's available now. Although waterproof bags are cheaper, they can sometimes be clumsy and of inferior quality. And while dedicated underwater housing lets you dive deeper, it is less mobile and much more expensive.
To start, all you need is to do is build your own kit to suit your gear. Kit prices start at $190.