In string theory, one of the many vibrational states of the string corresponds to the graviton, a quantum mechanical particle that carries gravitational force. Thus string theory is a theory of quantum gravity.
Their average web application development cost is around $500K and their staff or contractors' salary is in the six figure plus range. Their proposals are usually based on a lot of fluff with the development rate ranging from $400 - $800 per hour. These types of companies focus on custom development.
A good developer costs between $80 and $180 per hour. The good ones are always on the higher end of the range. From our own experiences, it is completely worth the money if you can find a developer that you can count on. Depending on the complexity of your website (the number of plugins you are using, the amount of custom coding you have), your annual maintenance cost will vary.