Using a crate to mail your stuff to the Netherlands
Lots of options are available to ship, after reviewing what would work for our family we chose Air Freight, see the details
So there are a few options when moving to another country to get your household goods moved safely. We just finished packing our crate (shown above, next to furry "helper"), and while the move is still ongoing I thought I'd put down what we learned from the process. Chime in to the comments if you want to share your journey or ask questions.
Our process took 3 weeks, with my wife (who has an illness) helping as much as she could, but a large chunk of the work being done by myself. We chose not to ship our furniture as we'll be renting our home furnished after we leave (until we can buy a new home in NL and sell). We made about $3,000 from the yard sale, mostly a few of the big ticket items, and spent about $3,500 on shipping and shipping supplies. There are ways to do things cheaper, and ways to do less work and pay more, but the numbers might help for reference for a 4 person family without furniture (which can cost a lot more).
First Round of Sorting
Our family of four had been living for 15 years in our US home. Lots of stuff can accumulate. While you could ship everything and sort it out later, wife and I agreed it would be cathartic to take the chance to purge a bit. We got trash bags for anything that would have no value to anyone, and a bunch of U-Haul boxes for things that might have some value (relatively cheap, lots of sizes).
Then, with the help of our kids, we went room to room and trashed / put in sale boxes everything that we no longer needed (it was a lot), If it wasn't sentimental and cost less than $3 per lb, then it would go in the sale boxes (and we could get new stuff on the other side).
Garage Sale day
We put up signs around the neighborhood, and posts in Facebook groups as well as Next Door (which brought a surprising amount of traffic) advertising all the things, including the big ticket items (I had an E-Bike, and all my Dewalt tools that weren't making the trip) to try and snag shoppers. Pulled all the U-haul boxes out onto the driveway and lawn mostly sorted, and with colored stickers on the boxes for prices. We had the prices on a marker board next to the stickers and lowered the prices throughout the day. Ended up doing 2 days of garage sale but it was nice, friends and folks from the neighborhood stopped by to chat, pick up things they could use and it felt good. We also made a few bucks which helps.

Towards the end of the second day, most of the items that were under $10 were marked as free, we listed on the local "Buy Nothing Group" which brought a lot of people who needed lots of things and helped with some of the misc. volume.
Goodwill
About half the volume went in the garage sale, we then loaded up any boxes that had stuff that Goodwill would take and made a goodwill run, which left only a few specific items of value
Air Freight
We chose this route as it's quick (1-2 weeks), relatively little jostling (door to door, pallet / boxes might even end up on the same plane you are on), and relatively cheap ($3 / lb was what we were given as a quote). We chose to use ExpatShipping.com, so far they've been easy to work with, sent a list of what we could and couldn't send in the box, and helped us along the way. The process was simple:
- Buy the right size crate / pallet on uline.com - we went with the 60x48x48, though standard pallet sizes may be cheaper as our largest item was 56" long.
- Crate came 1-2 days, putting it together was relatively easy, snapping and bending metal holders into place
- Packed everything in boxes and Jenga'd them in, it's good to put heavier boxes on the bottom, and to make sure there is no space to shift (I actually used some of my clothes and sheets to make sure everything was nice and tight).

ExpatShipping is scheduled to pick up our box Thursday, and we are hoping it will arrive shortly after we do next week, door to door. I ended up with an extra pallet from u-line that I'm going to have to take to the dump to recycle which is kind of annoying, but otherwise pretty smooth.
On the plane
Since you are flying too, you can pay for checked luggage, but take a look as the price isn't always worth it, especially considering that you'll be responsible for the "Handling" (to and from the airport). For instance KLM is $240 for an extra 50lb luggage or almost $5 / lb, but when we looked some airlines (like SAS) had the option to get backs only for one leg of your flight (the to Amsterdam part) and it was cheaper ($80 per additional checked bag). Still, with the kids, the wheel chair, and all the other chaos we tried to minimize checked bags.
Because shipping anything illegal risks the whole thing being sent back (no refund!) you should take anything questionable (medications, etc) in checked or carry on luggage, see the list provided by your shipper.
For everything else
Box is locked down now, but there is likely to be more things. You can ship individual boxes, FedEx / UPS / USPS / DHS, for smaller items flat rate international priority can be a good deal via USPS. One tool that I found helpful is GoShippo - sign up for a free account, and it will allow you to get comparisons for your package to help you find the best way to ship cheaply.
Roads not taken
- Container Shipping: Go by slow boat. Much cheaper, (0.50-1.50 / lb) you can get a FCL (Full container) if you want to move furniture or have lots of stuff, or a shared container. Costs may be higher as you'll have to find handling to and from the docks. Slower, takes weeks instead of days compared to air freight.
- Pods: Big metal pod delivered at your house (various sizes), load it up, and call to have it whisked away. This can be easier, tends to be a bit more expensive than air freight if you build your own container, and also tends to be slower (usually by slow boat).
- Van Movers: Probably the most expensive route, home to home (vs door to door), can even help with packing and unpacking in case you need that level of assistance or find it worth it. Some of the other options can be helped by calling local muscle to help with the packing part, but we didn't want folks helping us pack our underwear :)