The concrete for your project is measured and sold by volume, but the area of your site is also important in planning for the installation. Naturally, the overall cost of the job will increase with its size, but in some cases the cost per square foot goes down as the scale of the job goes up. Cost Comparisons
When my dogs are kept indoors, I let them out every 4 hours to use the potty. No more than four hours though, because I don't want to make them hold it any longer than they have to. Occasionally though, I'll be gone for 8 hours and I'll leave them inside, and they're fine. I walk my dogs once a day for exercise.
The rule of thumb for crating is no longer than one hour per each month of age, up to nine to ten hours maximum (the average work day). Each session should be preceded and succeeded by an hour of aerobic exercise. If this is too long for your dog, hire a dog walker to exercise him midday.