I have a GFR of < 5 and still work a full-time job. It helps that my job is most cerebral (I can work from home most of the time and work on a computer all day) - a physical job would be a problem!
I'm on PD which allows me to travel more easily for work and I can fit my life around my dialysis without too much trouble (I take an exchange bag everywhere I go just in case I get stuck somewhere).
I agree with Charlie to start dialysis now if you are not feeling well. You will feel better and be in a better place to determine the right work environment for you once you know what is entailed in dialysis. You CAN work on dialysis, it just takes some planning and organization!
If you'd like to know specifics of how I work on PD, PM me
Lane