How to correctly formulate the price for the bookmaker's parser?

Question

Freelance

Please tell me what price I should charge the client for parsing a bookmaker's office, the complexity of which is at an average level.

What I did:
- Found a way to bypass CloudFlare protection and get data;
- I was able to decipher the response of the request to their resource;
- Found their API and now I can parse data for all sports (except dates and times);
- Found API request configs;
- A script was written to receive data;

In total, it took me about 20 hours to complete everything.
The client is a foreigner, I offered him $500 for work, taking into account the commission of the freelance resource ( $100), he says it's expensive. Despite the fact that he will receive data for 3-4 bq, since they use the same API, i.e. it will get access to the API.

Answer 1

The price must be set before work starts. Or work hourly. And now it remains only to bargain in the hope of selling what you have done at a higher price.
$500 is even a small price tag.