High-profile slots on major networks can still cost tens of thousands, but local cable spots can be secured for much less.

Don't forget the cost of making the ad itself. High-end commercials can cost upwards of $40,000, though many small brands now use high-quality smartphone footage or stock video services for a fraction of that cost.

The workflow for buying TV ads online is generally consistent across platforms:

You will need a high-quality video file (usually 15 or 30 seconds). Most platforms have strict technical requirements for resolution and audio levels.

Are you looking to launch a campaign for a or a national brand ?

While costs vary wildly based on the network and time of day, online buying has lowered the barrier to entry: Often range from $20 to $50 CPM.

Instead of just picking a "show," you pick a "person." For example, you can target "Sports fans in Chicago" or "First-time homebuyers."

Buying TV ads has evolved from a process of "handshake deals" and complex agency contracts into a streamlined, digital experience. Today, you can buy television airtime with the same ease as purchasing Facebook or Google ads through automated platforms known as programmatic or self-service TV advertising.