Wages, signing on fee & agent fee

I tried to sign Messi with Man Utd when i had just started the game with a bid of £80mill which to my surprises was accepted but he wanted £400k in wages, £20mill signing on fee and his agent wanted £18mill

I can't get my head around the wage demands from the Messi's, Ronaldo"s etc which make them impossible to sign as the teams budget goes up to £250k a week and signing on fee and agent fee no more than £7.75mill

Its not fair