iPhone xr in the netherlands

At iPhone Xr launch, Apple is not offering an unlocked version of that phone. You need to wait until a fully unlocked version is available. And please note that iPhone warranty is NOT international. Should anything go wrong with a phone you buy in the US in the Netherlands, the phone will have to be physically returned to the US for service. It can't be shipped and Apple won't ship it back.

Be careful. When you say your network provider is compatible with iPhone Xr, that would be for the model Apple will sell in the Netherlands. That does not guarantee one purchased in the US is the same model. Apple does sell different models for different countries.

OK.......It's your money. I always do my best to encourage people to avoid any chance of making a buying mistake by purchasing their phone in the country they live and will use the phone. Buyer Beware is a true and valid statement in this type of buying decision.

You're welcome. I encourage to think about this.

The most often stated reason for buying a phone in the US is cost savings. That's nice until you take into consideration that if you suffer any breakage or issue with the phone, you can't get support where you live. You have to bring the phone back to the US, or ship it to someone you know in the US for them to take it to Apple for support. That costs money and time eating away at the initial cost savings.

Point two. Daily people come here to the forums because they bought a phone in one country, only to learn it's not compatible with the service providers in their home country. They in essence bought an unusable device and often they're past the return date where they did purchase it. And they have to figure out how to get the phone back to the country of purchase if they are within the return window. Again, costing them time and money.

That depends on exactly which model iPhone you purchase. See this document: iPhone - View countries with supported LTE networks - Apple

You'll need to make sure the phone you buy is compatible with the networks in your country. Your cellular provider should be able to tell you.