A shop is not a website with a buy button. The money in it sits in product data, payments, delivery, and the cost of every future change.
What you are actually buying
On a normal website the most expensive mistake is bad copy. On a shop the most expensive mistake is a structure that cannot hold your catalogue a year from now.
Almost every failed shop fails in one of three places: product data is maintained by hand and nobody has the time; payment or delivery does not behave the way customers expect; or the old product URLs vanished during a migration and all accumulated traffic went with them.
What each budget realistically buys
300 – 1 000 €
A hosted platform with a theme, manually entered products, standard payments. Works for a small catalogue that rarely changes.
2 000 – 6 000 €
A custom category structure, a link to inventory or accounting, sales tracking configured, migration from an old shop with redirects.
8 000 € +
Thousands of SKUs, several languages or markets, ERP integration, custom pricing and stock logic.
The first questions
E1
How do the products get in, and who maintains their data afterwards?
Why you ask
The import is a one-off task. Maintenance is daily, forever, and it is almost never in the offer.
A good answer
Asks how many products you have, where the data comes from, and whether it changes automatically. Proposes a link to the system you already keep them in.
A bad answer
"You will upload them through the admin panel." For 40 products that is fine. For 4 000 it is months of work handed to you.
How to check
Ask them to load ten of your real products before you sign. You will see how long one takes and can multiply it yourself.
E2
Which payment and delivery methods will be connected, and who negotiates them?
Why you ask
Every courier or payment integration is separate work, a separate contract and sometimes a separate fee. A missing popular method is a real loss of orders.
A good answer
Names which methods are in the price, which cost extra, and states clearly that the contracts with the courier and the bank are yours.
A bad answer
"We support all methods." Platform support and a configured connection to your account are different things.
How to check
Place one real order with a real card after launch, then refund it. If refunds do not work, you will find out from a customer.
E3
If I have an existing shop, what happens to the product URLs?
Why you ask
This is the most expensive mistake on this entire site. A shop migrated without redirects loses its accumulated traffic overnight, and recovery takes months.
A good answer
Uses the word "redirects" without prompting, explains that every old URL gets a new one, and plans a check after go-live.
A bad answer
"The new shop will be better, Google will find it." It will. It will also be starting from zero.
How to check
Save ten URLs of your popular products before the migration. After launch, open each one. Every one should land on the same product.