Marketing firms a scam?

I was thinking of hiring one of the local marketing firms to market my website I do freelance industrial design, Ive read some pretty messed up feedback for marketing firms being rip offs. Anybody ever promoted themselves through marketing firms and saw results?
Answer #1
I’ve never used one before, but it’s more of a pay a lot and gain little kind of thing.
They aren’t “scams” because they probably do some work, but they do charge a lot so it’s not really worth it.
This is just my five cents.
Answer #2
I see appreciate your feed back thanx a lot mate
Answer #3
how about ask what sites they worked on.
find site and see what you think.
any parish newsletters?
often cheap to advertise but can reach
loads.
either way good luck.