Hi I recently purchased a 2001 Celica GT for 2k with only 20k on a rebuilt engine but the only problem is that I've discovered the car has no rocker panels. They've been completely destroyed by rust. Just a couple taps to the side skirt and MOUNTAINS of rust fall from the panels https://prnt.sc/k-_2wkRgkVQW . How much would it cost to fix on both sides and how immediate is the problem?

Mainly got the car as a place holder for a year or two while I accumulate parts to fix my WRX sti. Original owner of the celica said he'd give me the money back if I really didn't want it. Trying to see if this is worth giving the car back or worth fixing, or if it won't give me trouble for a year or two.
More pics: https://prnt.sc/ncGujoxEZKaq https://prnt.sc/KbnLxi6gSH7S