Do not spend coins on speeding up a job, such as building contracts hiring new units. By remaining patient you will be able to keep more coins. For fighting purposes, consider hiring the three units. For carrying cargo, hire vehicles. You can also hire lawyers for legal defense and more debt collectors to extort more protection funds from other players. Money is required to hire more bikers. Buildings can generate more money. You can also upgrade them to generate even more resources. Keep upgrading your bar, club, casino and other cash producing buildings.
Respect
Maximize your respect level as often as possible. Respect is required to unlock more cities. The faster you increase it, the more actions you can do and more things that can be unlocked.
Units
Spend your money by purchasing units. Manage your first three units as your biker units. Examine their stats to check their attack, health and defense then start training. The more of them that you train, the stronger your gang will be. The number of units is more important than strategy.