Overall I try to avoid working for independent schedulers. All too often it seems to just add another layer of bureaucracy to getting the job done that I find as annoying as 'phone trees'--an expedient solution for the company but not for the user.
With few exceptions, the majority of the work I perform has a 'window' of at least 3 days. My absolute best companies give me a week to 10 days. Interestingly those companies are neither self assign nor do they take more than 30 days to pay. Their interest is in getting the job done and done properly. They are willing to pay appropriately for that and work WITH shoppers and they are selective about who they assign work to in order to have that happen. It is a different philosophy and business model than a whole lot of companies out there and they can do it because they screen so closely folks who apply to work with them.
Obviously the 3 day window is very helpful for scheduling work. I always try to do the work in the front end of the window if humanly possible since who knows what may happen tomorrow?