For most platforms, the answer is no,  if you are running the ads yourself,  you can usually spend as little or as much as you like. Some exceptions for this are LinkedIn Ads where you usually require a minimum spend per ad.

Of course, the more you spend the more results you’ll obtain, however, don’t be fooled. It is not always about the amount you spend, a lot of the time knowledge beats budgets, but you do need to "pay to play" so if you do not have skin in the game you will not get any or obtain very little results.

You could spend a small amount but have an amazing ad that is displayed in your ideal service location and generates a fantastic amount of high-quality leads. 

ReLATED ARTICLE: 'What Are The Different Types Of Google Ads?'

With paid ads, you can set a daily budget and have control over the CPC (Cost-Per-Click) CPM (Cost-Per-1000 = Impressions), and pause the spend at any point.

You can also use the system to pause any ad spend during periods when people are less likely to be searching e.g. overnight. 

Please note, if you are looking for us to run your paid advertising for you there is a minimum monthly spend.