When it comes to labor charges, it varies from one agency to the other. Same is the case with raw materials. moreover it also includes unforeseen expense like transportation, moving costs, wastage, cleaning & disposal, additional visit expenses, additional secondary material costs like masking tapes, special tools, specialized labor or consultants, and the list goes on...

In a country like India, keeping track of all these expenses is practically next to impossible, especially when the transactions are made in cash, or like in certain cases the value of the service cannot be tallied with money!

Although, the client can ask for the material and labor costs along with contingencies (unforeseen expenses) which can be a certain percentage of the total cost.

The best way to proceed out of this with minimum frustration, is to work with an architect who is knowledgeable, skilled and whom you can trust.

I hope this was helpful.