Are there any third party widgets or alike i can add to sell ad space on my website?

Im still under construction and all that and it is going well (so far, knock on wood) and while i know i have to export this project for conversion to wordpress or other host with unlimited CMS items. I was wondering if anyone knows any open source or reasonably priced widgets or alike that help me with selling ad space. Such as banners, and before video ads which this site is going to host through a 3rd party CDN

I have the same question.

I want to sell ads directly to clients. A client would pay for a number of impressions (like 1,000 impressions). The ad would show on page load, until it hits that number. If the ad is the only one in a particular spot, then it’s the only one showing. Or if others also buy that spot, then the ads would each take turns showing.

If anyone has any advice or direction, it’s much appreciated!