Will be cool but god damn that's a lot to pay for a rusted out KE70. Mine I just bought was $1200 with rego and RWC with only spot of rust below the fuel door.
My old one I gave up on was rusted where your's was looks like all the same places around the boot. got much down the bottom where the two panels meet behind the bumper? or down the bottom sides of each side of the boot behind the rear wheel arches? Also where the rubber drain plugs are behind the rear arches for the boot?
You have a LOOOONNNGGGG road ahead of you if you plan to fix all that up right. I gave up on repairing it and just cut the whole ass end off and used a little bit better ass end which still needed repairing and welded in some new panels. I got to the point of bogging and did that then just decided to buy a car in good nick.
Its hard to find panels for those boot sections not rusted. Even bought some off members from interstate on here that said yeah mate the car has no rust at all so they send me the panels that they cut off and once I get them they'd been repaired before or had rust in them.
Check my old page if you wan't pretty sure you'll be doing along the exact same lines. Page 8,22 and 23 is where you wanna look.
All I can say is I hope you're well motivated!