How to build a business AI stack for under $100 a month

There's a myth that doing AI "properly" means a stack of $200 subscriptions. It doesn't. Most small businesses get 80% of the benefit from a handful of tools that total under $100 a month — and often less, because the free tiers are better than people expect.

Here's how to build that stack without overpaying, in the order that actually matters.

Start with one assistant, not five

Your first and most important tool is a general AI assistant — ChatGPT or Claude. It writes your emails, drafts replies, rewrites copy, summarizes documents, and answers "how do I…" questions. One good assistant replaces the urge to buy a separate writing app, a separate summarizer, and a separate "email tool."

• Budget line: $0–$20. Start on the free tier. If you use it daily and hit limits, ChatGPT's new $8 Go plan or the $20 Plus/Claude Pro tier covers almost everyone. (See ChatGPT's $8 Go plan — is it enough?.)

Resist adding a second assistant. They overlap almost entirely.

Add design — usually free

For graphics, social posts, and simple visuals, Canva has built-in AI (Magic Design, background remover, brand kits). The free tier handles a surprising amount; Pro is about $15/month if you need brand kits and premium AI features across a whole brand.

• Budget line: $0–$15. Most solo owners start free.

Cover customer questions with chat

If customers ask the same things — hours, pricing, availability, returns — a website chat assistant like Tidio deflects them around the clock. The free tier answers basic questions; paid tiers add more AI conversations.

• Budget line: $0–$29. Start free, upgrade only when volume justifies it.

Automate the busywork last

Once the above is working, connect it. A no-code automation tool like Make or Zapier routes enquiries into one inbox, sends follow-ups, and logs leads — no code required. Entry plans start around $9–$20/month, and the free tiers handle low volumes.

• Budget line: $0–$20.

A realistic under-$100 stack

Add it up and a complete, genuinely useful stack looks like this:

• Assistant (ChatGPT/Claude): $0–$20
• Design (Canva): $0–$15
• Customer chat (Tidio): $0–$29
• Automation (Make/Zapier): $0–$20

That's $0 to about $84/month — and many businesses run the first few months almost entirely on free tiers, paying only when they actually hit a limit. Compare that to the trap of five half-used $20 subscriptions, which we unpack in Audit your AI subscriptions.

The rules that keep it cheap

1. Free until it hurts. Start every tool on its free tier. Upgrade only when a limit blocks real work — never to "future-proof."
2. One tool per job. One assistant, one design tool, one chat tool. Overlap is where money leaks.
3. Automate what's repetitive, not everything. Automation earns its cost only where you're doing the same thing over and over.
4. Right-size the tier. The $200 "power user" plans are for all-day heavy use, which most small businesses simply don't have.

Let us assemble it for your business

The exact tools shift by industry — a restaurant's cheap stack isn't a law firm's. Our Business AI Plans give you the precise stack for your business at $100, $200, and $500/month tiers, with live prices and setup steps for each — a $99 one-time setup, with an optional $29/month subscription that keeps it current. Or take the free 2-minute AI plan finder and we'll build the under-$100 version around what you actually do.