Hello, and thanks for your question.
Final grade may mean different things to different people. However, it is generally accepted that final grade means as flat and smooth as possible, hence the name "final". Practically speaking, final grade means that it is ready for seeding, or sodding. If the ground is wavy or has large chunks of material throughout, that is not acceptable. You have every right to complain. You probably don't have any recourse now that you have done the work yourself, but you might be able to convince the contractor to give you a small discount for not completing the work. It's worth asking, anyway. Let me know if you have any further questions.
Mark
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Handyman
Done it all - carpentry, electrical, remodel - commercial & res. maintenance