A custom GPT is one of the more useful things you can build for your business right now. It’s also one of the most talked-about and least understood. Here are the questions Dear John gets before most projects start.
What is a custom GPT?
A custom GPT is an AI assistant built to work specifically for your business. It knows your products, your services, your tone of voice, and the kinds of questions your customers or team ask. You use it the same way you’d use ChatGPT — type something, get a response — but instead of a general-purpose tool, you’re talking to something that knows your business.
Think of it less like hiring a new AI and more like training an assistant who’s read everything about your company before their first day.
What can a custom GPT actually do?
Depends on how it’s built. Common uses include answering customer questions on your website, helping your team find information quickly without searching through folders, drafting emails or proposals in your voice, screening enquiries before they reach you, or walking a client through a process step by step.
The more specific the task, the more useful it is. A custom GPT built to answer questions about your service packages is more useful than one built to “help with business generally.”
How is it different from just using ChatGPT?
ChatGPT knows about the world in general. A custom GPT knows about your business specifically.
You don’t have to explain context every time. It doesn’t give generic answers that don’t apply to your situation. It doesn’t go off-script. If you’ve ever opened ChatGPT and had to type a paragraph of background before getting to the actual question — that’s the problem a custom GPT solves.
The difference in practice: a general tool gives general answers. A custom one gives your answers, without you having to explain context every time. More on what that looks like at Dear John AI services.
How long does it take to build?
A straightforward custom GPT — one task, one context, one audience — can be built and tested in a few days. Something that connects to your CRM, booking system or website takes longer.
Most Dear John AI projects get scoped after an initial conversation, because what makes sense depends entirely on what you want it to do. There’s no useful answer to “how long” without knowing the actual brief. Get in touch →
What does it cost to get one built in NZ?
It varies. A simple custom GPT built on your documents and FAQs is a small project. One that integrates with your existing tools, handles live website enquiries, and needs ongoing refinement is a larger one.
The best way to get a realistic number is to describe what you want it to do. Not “I want AI in my business” but “I want something that answers questions about my services on my website without me being involved.” That second version is something you can scope and price. Start that conversation →
Can a custom GPT connect to my other tools?
Yes, with the right setup. Common connections include your website, CRM, booking system, knowledge base, or Google Drive. This is typically done using APIs or connector tools like Zapier or Make.
Not everything integrates cleanly, and some connections need more work than others. But most of the tools NZ small businesses actually use — Xero, Calendly, HubSpot, Shopify, Google Workspace — can be connected. See how connections work →
Is a custom GPT the only option, or are there alternatives?
No, it’s not the only option. Google Gemini has an equivalent called a Gem — same idea, built on Gemini instead of ChatGPT. Microsoft Copilot has similar customisation options for businesses on Microsoft 365.
Which platform makes sense depends on what tools you’re already using and where you need the assistant to live. The underlying concept is the same across all of them: a general AI tool configured to know your specific business.
What if I already use ChatGPT — why would I need this?
Using ChatGPT well and having a custom GPT for your business are different things. One is a general tool you use manually. The other is something built for a specific job that works the same way every time, without you being in the loop.
If you’re already getting value from ChatGPT and want to stop re-explaining yourself every session — that’s exactly when a custom GPT starts to make sense.
Dear John builds custom GPTs and AI tools for NZ small businesses. Not experiments — things that actually get used. See how it works →
