You can run an open-source ad server on your own machine for nothing, or pay someone to run one. The software is not really the variable. Your time is.
What self-hosting costs
The licence is free. Everything else is not.
A server. A small VPS runs $5–20 a month. Ad serving is light work, so this part is genuinely cheap.
Setup. Installing the software, a database, a web server and certificates is a few hours if it goes well.
Updates. An ad server sits on the public internet and accepts uploads from advertisers. It is a security-sensitive thing to leave unpatched. Budget an hour a month, and an urgent evening whenever an advisory lands.
Backups. Your campaign history and stats live in that database. If you have not tested restoring it, you do not have backups.
Being on call. If it stops serving at 2am, every ad on your site is dark until you notice.
Honestly costed, that is $10–25 a month plus one to three hours. If your time is worth $50 an hour, self-hosting a small install costs $60–170 a month.
What hosted costs
A monthly fee, typically $10–50 for small-publisher volumes, and none of the above.
The trade-offs are equally real:
- You are dependent on someone else staying in business
- You are limited to what they built
- Your data is on their infrastructure
Which fits you
Self-host if you already run servers comfortably, you enjoy it, you need to modify the software, or a policy requires the data stay on infrastructure you control.
Use hosted if your time is better spent on the thing your site is actually about, you want it working this afternoon, or "an ad server that stopped at 2am" is not a problem you want.
The question that decides it
Not "can I run a server?" — most technical people can. It is: when this breaks in eight months, on a day you are busy, do you want it to be your problem?
If the honest answer is no, pay someone. If it is "I'd rather know exactly what's running", self-host and enjoy it.
Two things to check either way
Can you get your data out? Some hosted services will not export your campaign history on cancellation. That should be a dealbreaker — it turns a subscription into a hostage situation.
Where does it serve from? An ad server answering from one location adds latency for distant visitors, and ads sit in your page's render path. A single VPS in Virginia adds around 200ms for a reader in Sydney.