The cost of M&V can vary significantly from one project to another. You’ll need to get project-specific bids based on your individual design needs. Accuracy and cost of M&V plans are influenced by the following: 

level of detail and effort associated with verifying post-construction conditions;
number and types of metering points;
duration and accuracy of metering activities;
number and complexity of dependent and independent variables that must be measured or determined on an ongoing basis;
availability of existing data collection systems, such as energy management;
and the level of precision designed and specified into the system, and your confidence in the data analysis.