After having had a few cheap beaters, I'm of the opinion that keeping a 35 year old car that already has issues running is more expensive than buying a slightly more expensive vehicle with fewer to no problems.
I expect it would ultimately be more expensive than this Insight, after solving all of the mechanical issues:
https://athensohio.craigslist.org/cto/5890892887.html
A grid charger may well revive the battery in that car, but it can be driven safely without it, and Insights are pretty darn reliable. You might be able to low-ball the owner down to around $1500 (maybe even less) if you show him/her some other similar cars on Craigslist, and driven carefully, you can see 70-85mpg tanks even without the hybrid system active.