If you want to view your squad just click on the league that you are in and then scroll down to your team.
On the far right of your team is the players valuation. This should give you a rough idea of how much you need to spend. If you have a team with not a lot of money the best option is to try and loan good young players from the bigger teams. They want their young players to get experience and improve without the risk of playing them against the bigger teams.