Integrating AI with the apps you already use: Excel, Google Sheets, email, invoicing

Many business owners believe that to use AI they have to change everything: new invoicing software, a new CRM, a new way of working. In reality, most of the value comes from connecting AI to what you already use: your Excel or Google Sheets spreadsheets, your inbox and your invoicing software.

In this article we show you what integrating AI with your existing apps looks like, which tasks suit it, how it is done technically (briefly and in plain English) and what to check before you start.

What “AI integration” means in practice

AI integration means an AI model is given controlled access to your data and applications and can do part of the work a person does today: reading, extracting, filling in, checking, summarising and drafting replies.

The difference from an ordinary AI chat is huge. In a chat, you copy the text in, get an answer and copy it back out. In an integration, the AI works directly in your workflow: the email arrives, the information is extracted, the spreadsheet is updated, the invoice is prepared. You just check and approve.

At Neurotech we use a single AI model, Claude, developed by Anthropic. We connect it to our clients’ applications through n8n, an automation platform, and through MCP connectors, an open standard for connecting AI assistants to data sources.

Integrating with Excel and Google Sheets

In many businesses, spreadsheets are the real management system: stock, orders, customer lists, prices, attendance. AI can work with them in several ways:

• Automatic data entry. Data from emails, forms or messages lands in the right row by itself, with no manual copying.
• Cleaning and checking. Names spelt differently, incomplete phone numbers, duplicates, wrong codes. The AI finds them and flags or corrects them according to your rules.
• Summaries and reports. “Which products sold best this month?” or “Which customers haven’t ordered for three months?”. You get the answer in words, not just figures.
• Categorisation. Enquiries, complaints or expenses sorted into categories automatically.

Google Sheets is usually easier to integrate, because it lives in the cloud and has a documented programming interface. Excel files stored locally on one computer are harder to access automatically. If the file is in cloud storage, things become much simpler.

Integrating with email

Email is where the most time is lost and where the most useful information is hidden. A few examples of what AI can do:

• Sorting and prioritising. Important messages (quote requests, complaints, payments) are separated from the rest.
• Extracting data. From a quote request, the AI pulls out the products, quantities, deadline and contact details and puts them in the spreadsheet or CRM.
• Draft replies. For frequent questions, the AI prepares a reply in your company’s tone, and you just read it and hit “send”.
• Attachments. Invoices, orders or contracts received as attachments are read and the important data is extracted.
• Follow-ups. If a customer hasn’t replied to a quote after a few days, you get a notification or a draft follow-up message.

The rule we recommend at the start: the AI prepares, a person sends. Once you trust the quality of the replies, you can let certain types of message go out automatically.

Integrating with your invoicing software

Most modern invoicing packages allow external connections, through an API or through file import and export. That opens up a few useful possibilities:

• Invoices prepared from orders. An order confirmed by email or WhatsApp automatically becomes a draft invoice, with the customer and products filled in.
• Tracking payments. The list of unpaid invoices is checked regularly and customers receive polite reminders.
• Incoming invoices. Supplier invoices received by email are read and entered in a register, ready to send to your accountant.
• Monthly reports. A summary of what was invoiced, what was paid and what is outstanding.

One important point: invoicing is subject to tax rules (in Romania, for instance, the ANAF e-Factura system). The AI prepares the data, but final issue and checking stay with you or your accountant. A good integration shortens your work; it doesn’t take away your responsibility.

How integration is done, in brief

Without going into technical detail, every integration goes through the same steps:

1. An inventory of your applications. What you use, where the data is and who has access to it.
2. Checking the connections. For each application we find out whether it has an API, an official integration or at least a data export.
3. Choosing the workflow. We start with a single task, the one that takes up the most time.
4. The build. n8n connects the applications, Claude handles the understanding part (reading emails, extracting data, writing replies), and sensitive data is kept in a database on servers in the EU.
5. Testing on real data. We run the workflow on real emails and documents and check every result.
6. Launch with human approval. At first, everything that comes out of the workflow goes through a person’s hands.

Example of a complete workflow

Take a distribution business that receives orders by email every day, in different formats: some in the body of the message, others in an attached spreadsheet, others as a photo. An integrated workflow would look like this:

1. The email arrives in the orders inbox.
2. Claude reads the message and the attachment and extracts the customer, products and quantities.
3. The workflow checks in Google Sheets whether the products are in stock.
4. A draft invoice is prepared in the invoicing software.
5. The person responsible gets a notification: “New order from customer X, everything in stock, invoice ready to check.”
6. The customer receives the order confirmation.

What used to take a person 15–20 minutes per order becomes a one-minute check.

When integration isn’t the answer

• The data is chaotic. If every spreadsheet has a different structure and nobody knows which version is correct, sort the data out first.
• The application doesn’t allow connections. Some older software has no way in at all. Sometimes it is worth replacing; sometimes there are workarounds.
• The volume is small. A few emails a week don’t justify an integration.
• You already have too many applications. Sometimes the better solution is a single custom-built ERP or CRM application, with AI built in from the start. That is what a chain of patisseries in Sibiu did, for example: it now has its own ERP linked to an AI voice agent.

Mistakes to avoid

• Starting with every application at once. A workflow that links five applications on day one is hard to test. Start with two and expand.
• Letting the AI send on its own from day one. A few weeks of human approval show you where the instructions need adjusting.
• Not deciding who is responsible for the workflow. Someone in the business needs to know what the integration does and who to call when something goes wrong.
• Not planning for exceptions. What happens to an email the AI doesn’t understand? A good workflow sends it to a person rather than ignoring it.

Data security

When AI is given access to email or invoices, the natural question is: who else sees this data? A few principles we apply:

• access is minimal: the AI sees only what it needs for its task;
• business data sits in Supabase, on servers in the European Union;
• according to Anthropic, data sent through the commercial API is not used by default to train models;
• every important action leaves a trail you can check.

The full details are on our data security page.

What it costs

At Neurotech, a process automation starts from €1,200 and a custom ERP or CRM application from €2,500, excluding VAT, paid in instalments tied to deliverables. Monthly costs (infrastructure, usage, maintenance) depend on data volume. To judge whether it is worth it, work out how many hours a month your team loses to manual data entry and to hunting for information in emails.

Next step

If you want to find out what can actually be connected to your applications, take a look at our automation services or book a free 30-minute call. Tell us what you use today and we will tell you which workflow would give you the most time back.