CPM relates to cost per thousand so I guess the answer would be at least 1000 to be taken seriously. 25 000 would make you an okay amount of money. Even if you don't receive that many visits you could ask local businesses if they want to advertise.
There are companies out there that are willing to advertise on sites that get 10k unique visits. But it really depends on the niche. The higher your traffic, the higher your advertising rate should be.
There is lots of factors involved in this, if you have 5K targeted visitors, who are really interested in your niche, you can have great start, but more is always better
It boils down to the companies you are thinking about. Sometimes it's the relevancy of traffic that matters, not the quantity at all times. Some prefer to get visitors that are related to their niche.
In a company, I think the build many website to get more customers and of course to generate traffic. The also use their website to become popular in the web.
Depends totally to what marketing field you want to compete.
Search your keywords in google and watch how many competitors site/webpages you get.
Research how many searches per month people will do for your keywords.
You can find the info from google adwords.
There are companies out there that are willing to advertise on sites that get 10k unique visits. But it really depends on the niche. The higher your traffic, the higher your advertising rate should be.
There are reputable sites or blogs that receive thousands of visitors daily. I would say if you have a site which receives that kind of traffic and that traffic is targeted, I think that companies would be pleased to advertise on your site. When it comes down to traffic what makes the difference is when it is targeted because targeted traffic is far more likely to convert.