Inflexibility is another challenges. Map out your plan and continually review your plan versus reality. Be willing to make changes when you see your plan is failing. Without a plan or refusing to gauge success against your plan has doomed many companies to continue down a road to failure. Have a willingness to change the plan and learn. Fail teachs you a lot.
Understanding your manpower and cash issues can determine the success or failure of any project. Do not overestimate your capabilities or underestimate your cash flow. Map out the details of all of the projects going on and what you are bidding that could happen in the near future.