Heres the data:
In format Cost (approx inc rounding), Output, Upgrade Time, iph, $cost per $iph gained
Level 1 -- £55,000,000 ----- $843,000 ----- 24h -- $35,125 ---- $1565
Level 2 -- £91,700,000 ----- $1,686,000 --- 30h -- $70,250 ---- $2610
Level 3 -- £152,800,000 ---- $2,950,000 --- 36h -- $122,917 --- $2900
Level 4 -- £254,700,000 ---- $4,636,000 --- 42h -- $193,167 --- $3626
Level 5 -- £424,500,000 ---- $6,744,000 --- 48h -- $281,000 --- $4834
Level 6 -- £707,500,000 ---- $9,273,000 --- 54h -- $386,375 --- $6714
Level 7 -- £1,179,200,000 -- $12,223,000 -- 60h -- $509,292 --- $9592
Level 8 -- £1,965,300,000 -- $15,595,000 -- 66h -- $649,792 --- $13988
Level 9 -- £3,275,500,000 -- $19,389,000 -- 72h -- $807,875 --- $20722
Level 10 - £5,459,200,000 -- $25,290,000 -- 78h -- $1,053,750 - $22203
Approx Total Cost To Build & Upgrade - £13,565,400,000
Note: the last cash value will tell you how many hours it will take to get your cash back via collecting from this building, eg 1565 hours for lvl1, 2610 hours for lvl1 - lvl2 upgrade etc all the way till 22203 hours to get your cash for the final upgrade...divide by 24 for the number of days (65 days for lvl 1, 109 days for lvl 2, 925 days for lvl 10), divide by 168 for the number of weeks (9 weeks for lvl 1, 132 weeks for lvl 10) and so on....
Units:
Lvl 1 -- maple Rampager (Inf) 432/359
Lvl 2 -- maple Assault Vehicle (Gro) 504/550
Lvl 3 -- maple Dragoon (Inf) 699/750
Lvl 4 -- maple swarmer 1024a/952d
Lvl 5 -- maple missile tank 1526a/1109d
Lvl 6 -- maple daredevil 2001a/1425d
Lvl 7 -- maple squadron 2310a/2038d
Lvl 8 -- maple carrier beaver 2692a/2710d
Lvl 9 -- maple stroke force 3677a/2911d
Lvl 10 - maple wz-120 Titan 7016a/6160d
credit to edson & candyson & dledour & calvin98 & diverguy & my faction for some data