I made a spreadsheet and put part numbers, prices, venders and anything else I thought would be nice to have in it. You can move things around to set up orders by vender to break it into chunks to save on freight and what you can afford to do per bite.
Two years later I can't find it but it was a great way to plan for what was going to cost how much and where you are going to get it.
I packratted parts for 10 years before I started my swap, being able to afford it isn't really an issue a point IMO. Be patient and eventually you will get there.
Just a guess, I think about $2-2.5k got me on the road. New exhaust, carb, intake, water pump headers, electric fuel pump, radiator, cap/collar, efan and oil pump. Rebuilt dizzy. Starter, PS pump and FEAD came with $200 roller engine, $250 automatic trans with my stock t-case. Rear driveshaft was something like $180 to be retubed/lengthened and front was $50 to shorten.
Used stuff is hard to guestimate because you never know what kind of a deal you are going to get until you get it. Some people will all but give stuff away while others think it is gold.
And then after you are around it for awhile you go back in and change things, I changed to an Explorer FEAD (new belt, timing cover, tensioner/idlers, water pump and alternator) used HO cam, used E7 heads, flex fan... and I still want to put in an overdrive trans (which would mean new t-case and driveshafts again
)