1,120 citizens. 87 infra = 12.87 citizens per infra level.
5*100 for 3 million tech deals over 20 days will make about 7.5 million.
20 days of bills to pay with no infra upkeep. 7.5 million on infra, will result in 1,284 infra levels
1284 x 12.87 citizens per level
16525 citizens
lets say, what, $60 tax per citizen with all income improvements still in place
16500 * 60 * 20 (19 if you do not want to risk deletion)
19,800,000 for the 20 day back collection.
1033 infra purchased
2317 infra
2317 * 12.84 = 29,000
Only now would infra camps be even remotely useful. Destroying the income improvemnts would hurt a lot more.