Best AI for Marketing Ideas: Tested on 5 Service Niches

For marketing ideas, Claude (Opus 5) and ChatGPT are the two worth paying for — $20/month each. Claude is stronger on long-form strategy, offer construction, and campaign architecture; ChatGPT is stronger on raw volume, ad variants, and visual concepts. Add Perplexity Pro at $20/month for competitor research that cites its sources, and Google Gemini at $19.99/month if your team already lives in Google Workspace. For a US service business — HVAC, dental, personal injury, roofing, med spa — the working stack is one $20 subscription plus a 400-word context brief. The model matters far less than what you feed it. Below: the brief, a scoring rubric, honest costs, and the situations where this is a waste of your money.

The Ranking, By Job

Most comparison articles rank these tools as if "marketing ideas" were one task. It isn't. Here's the split that actually holds up in production work:

Free tiers are genuinely usable for a solo operator. If you're generating fewer than 20 ideas a month, don't pay anyone anything yet.

Your Ideas Are Bad Because Your Input Is Bad

The single largest quality difference between two people using the identical model is the brief. A prompt that says "give me marketing ideas for my plumbing company" returns the same seventeen suggestions everyone else gets: seasonal maintenance emails, Google reviews push, before-and-after photos, referral program. Those aren't wrong. They're just not *yours*, and they're already in your competitors' outputs.

Build a context brief of 400–600 words you paste at the top of every session. It should contain:

Feed that in, and idea quality changes measurably. In our own testing across service-business accounts, a briefed session produces roughly 2–3× more ideas that survive a strategist's first review than an unbriefed one. Building the brief takes 90 minutes once. It is the highest-leverage 90 minutes in this entire article.

The model is not the variable. Ninety minutes of writing down your own numbers beats any tool upgrade you can buy.

Score Ideas Before You Build Them

Here's what almost nobody publishes: generating ideas is now free and instant, which means idea generation stopped being the bottleneck around 2023. The bottleneck is triage. A single briefed session produces 40 ideas in about 25 minutes. A three-person service business ships maybe 4 marketing initiatives per month. You need a way to kill 36 ideas fast without agonizing.

Score each idea 1–5 on four axes, then multiply:

Anything under 100 (of a possible 625) goes in a parking lot document. Anything over 300 gets scheduled this month. This rubric is the part AI can't do for you honestly, because the model has no idea what your team can actually execute.

When This Isn't Worth It — Read This Before You Spend

This section costs us business, and it's the most important one here.

AI idea generation is close to useless if you have no way to execute. If you're a two-truck operation where the owner sells, dispatches, and answers the phone, 40 ideas creates guilt, not revenue. You will implement zero of them, feel behind, and conclude AI doesn't work. What you actually need is one channel run properly — usually Google Local Services Ads plus review velocity — for 90 days. Skip the ideation entirely.

It's not worth it if your fundamentals are broken. Ideas cannot fix a 68% missed-call rate, a booking page that takes 11 clicks, or a 26-hour lead response time. Industry lead-response data has been consistent for over a decade: contact within 5 minutes vastly outperforms contact within an hour. If you're calling leads back the next morning, no campaign concept saves that. Fix the phone before you buy the subscription.

The failure modes are real and specific:

Who should not hire an agency for this at all: businesses under roughly $400,000 in annual revenue, businesses without a working CRM, and anyone who can't name their cost per acquisition within $50. Agency retainers in this space run $1,500 to $8,000 per month. If you're not tracking CPA, you cannot tell whether that retainer is working, and you'll cancel at month four having learned nothing. Our pricing page lists real numbers, and our ROI calculator will tell you if the math fails — sometimes it does.

What It Actually Costs, End to End

Assume a $2M home services company running this in-house:

The honest comparison isn't tool versus agency. It's *whether anyone on your payroll will reliably spend those 8 hours*. Most owners won't, which is the actual argument for outsourcing — not capability, capacity. We wrote about that tradeoff in AI agency vs traditional agency, and the benchmark data behind these numbers lives on our AI marketing statistics page.

A 30-Day Plan That Produces Something

Run that loop four times and you'll have shipped 8 tested campaigns for under $2,000 in tooling and media. Two will probably work. That's a normal, good outcome — and if it isn't happening, the problem is your execution capacity, not your choice of model. If you want an outside read on which of those is true for your business, the free marketing audit will tell you plainly, including when the answer is "don't hire anyone yet."