in china, we call it a bag/briefcase company by direct translation. it is small in size, maybe set up by several people; it usually does not do business honestly, and does not have much assets(only a bag/briefcase in hand :-) ), it can disappear at any time with your money. as far as i know, in places like virgin islands, bermuda where regulations on corporations and finance is quite loose, there are many such kind of companies.

my question is what native speakers call it. do u have a specif expression for it?

seat-of-the-pants operation
but that may be not dishonest enough for your context:-)

dubious/sleazy operation

Perhaps a 'fly-by-night' business. 'Fly' here means to flee, to run away. They take your money, and run away secretly and unexpectedly.

Best wishes, Clive
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Fly by night business is unreliable because it has been recently established and may disappear at any time, thus is unreliable.
ClivePerhaps a 'fly-by-night' business. 'Fly' here means to flee, to run away. They take your money, and run away secretly and unexpectedly.
The term has some "seniority"Emotion: smile
I thought that this type of operation was called 'carpetbagging'. Similar schemes as described were commonplace after the American Civil War with unscrupulous Northern 'businessmen' moving in on the Southern States. The famous novel and film, the Carpetbaggers, was written by Harold Robbins and was said to be loosely based on the life of Howard Hughes.

The term arose because they only carried with them an old-fashioned bag made out of carpet material, didn't it?

In BrE it can also be 'here today, gone tomorrow'.
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No, carpetbagging is something else. Check it out at Wikipedia

Basically, that's someone who moves somewhere else to take advantage of the situation there. Now, we use it for a politician who moves to a district he's not from because he has a good chance of getting elected from that district. A carpetbagger doesn't intend to scam you, but will take advantage (perhaps unfair advantage) of what is in the place he moves to.

Originally, a shell company came to mind, but that's not right either.

I think the above-mentioned fly-by-night is as good as we'll get on this one.
ghost company
might work too:

fabricated for purposes of deception or fraud: We were making
contributions to a ghost company.

Thanks for the clarification, GG. If you look further down on the Wikepedia site, you can see that it has been used more generally in the UK and in popular usage but obviously has a more restricted meaning than I thought.
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