Not sure you have the know-how in-house to build a DR solution? Do not let this stand in the way of protecting your business.
There are plenty of resources available to help with this project. If you have a thorough knowledge of your technology, it may still prove beneficial to seek outside assistance with thorough knowledge of disaster recovery planning and rollouts.
Even if it is just to help draft or review your plans to be sure something was not overlooked, you will have justified the expense.
Remember, you don't know what you don't know.There are many who have done this hundreds of times and could be of great value in designing and even implementing your solutions.