Unrealistically optimistic figures, I'm afraid. The costs you mentioned would cover nothing more than a minimal prototype you can take to investors. For that cost this app can never be robust enough to make it in the wild. You also need to account for back-end service costs, which in an app coded in a rush (under such a constrained budget) will result in tens of thousands of $$$ in a matter of days. Apps are expensive for a reason. The initial $2000 cost you're describing would barely cover my time in meetings discussing the requirements, designs and accessibility implications.