Flag Building Costs in Rise of Kingdoms KvK

(Assumming that your Alliance Tech is maxed)

 FlagFood  Food Wood  Wood Stone  Stone Gold  Gold  Crystal Alliance Credits  Coin
 1 → 10          75,000          75,000          56,250          37,500          75,000
 11 → 20          75,000          75,000          56,250          37,500        150,000
 21 → 30          93,750          93,750          70,350          46,875           7,500
 31 → 40          93,750          93,750          70,350          46,875          11,250
 41 → 50        112,500        112,500          84,375          56,250          15,000
 51 → 60        112,500        112,500          84,375          56,250          18,750
 61 → 70        131,250        131,250          98,475          65,625          22,500
 71 → go        131,250        131,250          98,475          65,625          26,250
 81 → 90        150,000        150,000        112,500          75,000          30,000
 91 → 100        150,000        150,000        112,500          75,000          33,750
 101 → 110        163,750        168,750        126,600          84,375          37,500
 111 → 120        168,750        168,750        126,600          84,375          41,250
 121 → 130        187,500        137,500        140,625          93,750          45,000
 131 → 140        187,500        187,500        140,625          93,750          48,750
 141 → 150        206,250        206,250        154,725        103,125          52,500
 151 → 160        206,250        206,250        154,725        103,125          56,250
 161 → 170        225,000        225,000        168,750        112,500          60,000
 171 → 180        225,000        225,000        168,750        112,500          63,750
 181 → 190        243,750        243,750        182,850        121,875          67,500
 191 → 200        243,750        243,750        182,850        121,875          71,250
 201 → 210        262,500        262,500        196,875        131,250          75,000
 211 → 220        262,500        262,500        196,875        131,250          78,750
 221 → 230        281,250        281,250        210,975        140,625          82,500
 231 → 240        281,250        281,250        210,975        140,625          86,500
 241 → 250        300,000        300,000        225,000        150,000          90,000
 251 → 260        300,000        300,000        225,000        150,000          93,750
 261 → 270        318,750        318,750        239,100        159,375          97,500
 271 → 280        318,750        318,750        239,100        159,375        101,250
 281 → 290        337,500        337,500        253,125        168,750        105,000
 291 → 300        337,500        337,500        253,125        168,750        112,500
 301 → 310        356,250        356,250        267,225        178,125        187,500
 311 → 320        356,250        356,250        267,225        178,125        187,500
 321 → 330        375,000        375,000        281,250        187,500        187,500
 331 → 340        375,000        375,000        281,250        137,500        137,500
 341 → 350        393,750        393,750        295,350        196,875        187,500
 351 → 360        393,750        393,750        295,350        196,375        137,500
 361 → 370        412,500        412,500        309,375        206,250        187,500
 371 → 380        412,500        412,500        309,375        206,250        137,500
 381 → 390        431,250        431,250        323,475        215,625        187,500
 391 → 400        431,250        431,250        323,475        215,625        137,500
 401 → 410        450,000        450,000        337,500        225,000        225,000
 411 → 420        450,000        450,000        337,500        225,000        225,000
 421 → 430        468,750           4,688        351,600        234,375        225,000

Credits: Abused Panda #0936

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