Odoo offers dozens of apps: accounting, sales, CRM, inventory, projects, website, HR. Faced with that catalogue, many small businesses make one of two mistakes: they want everything from day one, or they open a free trial, click around for an hour, and close the tab. Either way, nothing moves. Here is the order I recommend to a company of five to thirty people that wants to get started without getting lost.
1. Start from a problem, not from the app list
The right first question is not "which modules do we need?" but "what costs us the most time or the most errors today?". In many small companies the answer is a single flow: a quote becomes an invoice, the invoice has to be paid, and the payment has to be found on the bank statement. If that flow runs through a spreadsheet, copy-paste, and reminders written on sticky notes, that is where to start.
Invoicing also has a regulatory reason to come first: since 1 January 2026, VAT-registered Belgian businesses must send and receive their business-to-business invoices in a structured electronic format, in practice over the Peppol network. We covered what still trips people up with Peppol in Odoo.
2. Draw the flow before you open Odoo
Take an afternoon with the two or three people who actually do the work, and draw the chosen flow on a sheet of paper: who does what, with which tool, and where information gets lost. That sketch becomes your specification, even an informal one. The method is in our article on mapping a process in one afternoon.
3. A first scope that fits in one sentence
Write the scope of phase one as a single sentence, for example: "Do quotes, invoices, payment reminders and bank reconciliation in Odoo." If the sentence needs three commas and an "and also", the scope is too wide.
What can almost always wait for a second phase:
- inventory and manufacturing, unless they are the core of your business;
- the website and the online shop;
- custom development and screens reworked with Studio;
- importing the full history of the last ten years.
A successful go-live on a small scope beats a big project that bogs down. The team gains confidence, and phase two builds on customer records and products that are already clean.
4. Test with your real cases, not the demo
Odoo offers a free trial, and its "One App Free" plan gives you one app, with unlimited users, on Odoo Online; the apps it depends on are included. To test an invoicing flow, that is enough.
The trap is testing with demo data. Take three real situations from last month instead: a simple invoice, an invoice with a down payment or a credit note, and a customer who paid in two instalments. Redo them in Odoo. Wherever you get stuck, you have a real question to ask instead of a vague impression.
Do not import your whole customer file yet. Deciding what to bring over and what to leave in the old system is a separate job, described in our article on the data to clean up before go-live.
5. Name an internal owner
An Odoo project without an internal owner becomes the consultant's project, and it stops when the consultant leaves. Pick someone who knows the flow, who will have a few hours a week during the project, and who can settle small questions without a meeting: product names, default payment terms, who approves an invoice.
6. Decide how you will be supported
A small business can set up a simple flow on its own. As soon as accounting, VAT or a data import come into play, a few hours with an integrator often save weeks of fixes. Before you sign anything, reread what to check before signing: edition, hosting, type of partner.
That is the work we do at z80: scope the first phase, configure, train the team and stay available after go-live. The details are on our Odoo deployment page.
7. Plan for after go-live
The day the team switches over is not the end of the project. The first month decides whether Odoo becomes the reference tool or just one more program next to the spreadsheet. We wrote a week-by-week plan for the first thirty days after go-live.
In short: one precise problem, one flow on paper, a one-sentence scope, three real cases tested, one named owner. With those five in place, phase two becomes a simple decision rather than a new project.