Good Deal or Not - 4plex built in 1935?

[Ivy Ford-Crafton]

1935 4 plex that I want to Buy and Hold.  Has a foundation issue but is fixable. Offered $750K but found out possible Repair costs could be $90-$100K to completely repair with the foundation being the most expensive($27K). Comps in the area are $550K - $1mil. There are a lot of houses being torn down and new construction thats driving the comps to $1mil. Total Rents $5585. I'm able to secure a conventional loan with 25% down and 30 yr mortgage. I recently started negotiations to bring the offer to $695K due to the condition. I think I'm needing a mold and termite inspection. Last tax value was $900K in 2019, but I truly believe its more like $695K which it was tax appraised in 2018. I'm not sure why the value tax appraisal increased so drastically when no updates or repairs had been made. So taxes went from $16,000 yr to $21,000. Good Deal or pass?