The building I've been waiting for, running numbers.. Might take a bit haven't had to do this in a while.
Unmodded Times
1. 24
2. 27
3. 39
4. 47
5. 55
6. 63
7. 71
8. 79
9. 87
10. 95
Unmodded Payouts
1. 17,647
2. 35,294
3. 61,765
4. 97,059
5. 141,176
6. 194,117
7. 255,882
8. 326,470
9. 405,881
10. 529,410
Modded costs.. around 63% cheaper
1. 450,000
2. 239,652
3. 335,512
4. 503,268
5. 805,239
6. 1,449,412
7. 2,898,824
8. 6,087,530
9. 13,392,567
10. 30,802,902