I’m no fortuneteller and I don’t have any special expertise in international trade, but I can report what I saw today.
I ordered a Chinese-made WWVB time signal receiver module from a Canadian seller on eBay. It cost $9.13. Here’s a screen shot from my order on eBay:
When I went back to check the order today, there was a note on the seller’s listing that it had been updated:

That’s about a 1000% increase.
Instead of raising the price, some international eBay sellers are just adding the tariff to the shipping cost (which I prefer because it makes it clear what’s going on and makes it easier to do price comparisons). Here’s an example of a radio I have:

Or how about $505 to ship a Tecsun S8800 from Hong Kong?
The title of this blog post is a play on a trade policy called “de minimus,” that allows Americans to order things from other countries, up to one package per day valued up to $800, with no import duties. That policy ends for China on May 2. The shipping country isn’t important; it’s the country of origin that determines the tariff.
My WWVB clock module should have shipped 3 days ago by eBay’s standard 2-day shipping policy, but it hasn’t. Supposedly eBay international shipping rolls up all taxes and duties into the selling price. So whether it will ever ship is an open question in my mind.
Update:
The eBay seller was kind enough to answer my query, informing me that the package had arrived in the US prior to the tariffs going into effect. It’s scheduled for delivery on May 9.c
Update 2:
I had a misunderstanding about how tariffs are working. The article above is correct as it stands, but it talks about two individual sellers who ship internationally direct to customers.
AliExpress is a supplier that I use for some radio-related items. Their model is to aggregate a number of orders into one shipment, which passes US customs and is assessed on the total value of the shipment. Once customs is cleared, the large shipment is broken up into individual packages and put in the mail stream. While there is indeed a 145% tariff, there is no $100 minimum per order or per item when items are shipped this way.