Facebook advertising can be set up with any budget. When you create a Facebook ad campaign, you specify a total amount you want to allocate on a daily basis or over the campaign’s lifetime. You also set your maximum bid, which is the amount you pay when your ad is shown or a viewer takes your desired action, such as clicking the ad. Facebook will not go over the budget you set for your ads. You can also edit your budget at any time.
Generally, according to the stories and discoveries making the news, you determine how much you want to budget on Facebook Advertisements. But this would vary depending on who you are trying to target. For example, you would want to spend more to get your message to folks from certain countries than you would for other countries. This is because many other folks or companies are also targeting the same countries and hence the competition.