there is certainly a single market for goods, services is far from complete

it makes the statement "four freedoms are indivisible" somewhat hollow, because there has never been full freedom of services

I ~~have been~~ was a consultant in the EU for about 3 years w/ clients in 7 different countries. All I (additionally) had to do was mark a checkbox on my income tax statements.

If that checkbox was all that held me from "full freedom", then I concede your point.

Can confirm on that the single market for services is far from reality.

Today, if I'm a consultant and have a consultancy company registered in EU country X, if I come to EU country Y to provide my services there, it's pretty likely that I will have to set up a separate company in Y or Y's tax people will be after me (that's currently the situation in UK for example).

I cannot confirm that. I found the tax agreements within the EU to be relatively easy in the EU & UK. Of course you deal with two authorities, so there is an additional benefit, but recognizing taxes paid in the UK with another country was not that hard.

Yes, there is no double taxation - but you essentially need to involve yourself with the tax authority of every country you are doing business in.

In a real single integrated market, I'd have company registered in country X, serve customers across entire Europe, but file taxes on the entire income in X only. I'm thinking they don't allow that because it would open doors to all kinds of tax optimization for the little people - ex. say UK workers would register themselves as companies in countries with very low taxes, and continue to work ("provide services") in UK. This kinds of schemes are allowed for the megacorps, but not for us regular folk.

"involve yourself" in this case is present the tax income declaration to the tax authority in the 2nd (3rd, etc.) country.

Hardly a cumbersome experience.

In practice, you need to learn the tax code to find most suitable form of conducting business. For example, in the UK if you know what you're doing, you'll pay ~20% tax on your income as a contractor. If you don't, you can easily end up paying something like 30+%.

Also, there are perpetual costs of having a company registered (such as monthly payments to an accounting company which handles paperwork, health care contributions etc.), so if you move around regularly between a couple different countries, you'll probably need to maintain a legal presence in each one, and thus have these costs multiplied.

> In practice, you need to learn the tax code to find most suitable form of conducting business.

That has not been my experience.

Not yet, anyway. There's still a lot of talk about it. I'm particularly interested in the ongoing talk about a single market for digital goods.

You can agree with the existence of a single market but find most of that quote flowery political rhetoric.