Make a list, divide it into sections, then prioritize each thing in the sections as to what it will do to get the car running, if that’s your goal. If you need to buy parts for a particular assembly that is the priority for that section, make it a priority to find and purchase those parts, or sometimes order them well in advance. Example….
Interior….
Seat covers
Door panels
Carpet
Headliner
Armrest bases and pads
Guages and dash
Now my prioritized list….
Seat covers and door panels have a 10 month wait time, not top priority to get it running, but need to be ordered for the future
Carpet can be there in 3 days, but not needed to get it running
Headliner…again, maybe 3 days out unless it’s a special order color. Not needed to get the car running, but needs to be done before you put the seats and carpet back in.
Armrest bases and pads..not a priority to get it running but if you don’t have them to open and close the doors to drive it to the body shop, find some used or buy them new
Guages and dash….top priority to get it running if it has electrical issues. Concentrate on that in your labor schedule
Do this for every area of the car, put prices and timelines on each item in your sections, then concentrate on the items that need to be addressed immedietly to get it running, and parts that take a long time to get. And spend the money you have accordingly so you have the stuff you need when you need it, and work on the stuff that you can while you wait.