Ask yourself, before you start a new church, whether your fellowship has local leadership that does just about everything in regard to serving. The involvement of all those who are converted is vital to the spiritual health of an individual and to a group. If it looks like your local group will not soon be changing how it operates, then it may be time to begin anew.
Are religious politics greatly decreasing your group's effectiveness? Christian leaders who are more concerned about their position and pet programs often resist God's spirit. They may even try to stop efforts by some to play a more active role in the local church. If you are in such a group, it might be time for a change.
Is sin openly practiced by some in the fellowship? Those Christians who habitually sin should not be allowed to come to worship services (1Corinthians 5:1 - 7). If such sins are allowed to exist unchallenged, it is likely time for you to move on.
Do you have significant doctrinal differences with other Christians with whom you meet? Disagreements can be worked with if the local group allows open discussions regarding its teachings and practices. If, however, leadership is unwilling to take seriously your concerns, you may be more comfortable elsewhere.
Do you feel that God is leading you to serve others in a unique way? Your ideas may be worth pursuing. If, however, you find your congregation less than enthusiastic (if not downright hostile) to your sincere plans, it might be time to start a church founded on freedom.
Bad Reasons
What are some bad reasons for people attempting to begin a church? Do they think they know just about everything important the Bible teaches and feel compelled to "bless" others with this insight? Do they believe God has given them some special prophetic insight that has to be heard? Is someone frustrated by not being recognized by the church? Beginning a new assembly based on the above reasons is asking for a great deal of trouble.
A desire to serve God and the brethren in love and a willingness to work hard are the foundation stones on which to start a church. While knowledge of the Bible is important, it is not the critical asset in creating a new fellowship. New congregations have a much easier time taking shape when people or families of the same mind all pitch in to do whatever work is needed.