Thomas Haas is a brilliantly designed card, considering who the character Thomas Haas is, and considering how playing Thomas Haas usually goes:

The corp installs Thomas Haas in a server. Advances him twice. Optimistically, the runner takes the bait and runs the server, paying their way through multiple ice. At the end of the line, the corp rezzes Thomas Haas, uses his Trash ability, and gets back the money back that they paid for him. Is the runner worse off? Maybe, but mostly Thomas Haas was a waste of their time.

Any corp dreaming of some crazy efficient burst of money from Thomas Haas, or dreaming of protecting themselves from Account Siphon by hiding some money on Thomas Haas, or even dreaming of surprising the runner by rezzing ICE that was just a little more expensive than the runner was counting on is going to be similarly disappointed. Those situations are possible in a game of Netrunner, but they are going to be few and far between. In more games, Thomas Haas is going to be a waste of your time.

What a perfect card for Thomas Haas, whose biggest character trait is that he is a waste of time loser.

I'm going to try to send him to Space Camp.

Thomas Haas is an unusual card. He appears to be an econ card, but in actual fact is a 'trick' / utility card.

He is not a normal econ gain card because each advancement on him costs a and 1, and eventually gives back 2, which is a net gain of 1 per - the same as simply clicking for credits. (Less the overhead cost of to install and 1 to rez).

So what is he actually for then?

In a glacier deck he can be installed and advanced in scoring remote to bait the runner into spending a lot of credits running him, thus opening a scoring window the next turn. Compared to using an actual ambush (like Aggressive Secretary), he is a low-risk bait, but with less payoff if successful. Low risk because regardless of whether he is run or not, he can be rezzed and then trashed to reclaim most of the cost invested in him.

However, this same role - of spending runner credits to open a scoring window - can now be better filled by Reversed Accounts in an expensive remote. Either the runner spends a lot of credits to access and trash this, or next turn the Corp can use it to make the runner lose a lot of credits. (GRNDL Refinery can also work if the Corp has a way to turn a credit lead into a scoring window, eg with Ash 2X3ZB9CY, or some big unrezzed ice installed).

Thomas can also be used as a secret credit cache to feign being poor. Once the runner approaches a piece of ice (and passes their last chance to jack out) he can be rezzed and trashed to gain credits then use them to rez that ice.

It is also possible to use a card that provides for advancing on Thomas Haas to turn those into real credits (eg The Root, Simone Diego). However, this is a convoluted setup for little payoff.

Overall, Thomas Haas is an interesting card, but it is only a very rare deck that he is the best choice for whatever effect you want him for.

Similar in ability to a GRNDL Refinery, this is a solid way to get a few credits when you have a defended remote server. One key difference makes this far more flexible, however. This card does not require any clicks to cash in, so if your server is compromised you can dump him for your money! However, the sheer amount of credits to advancement makes GRNDL Refinery much more cost effective if defended.

It's not worth it if you install-advance-advance, netting you a cool 1 with rez and advancement token costs, so plan to load it up. If you have any free advancement tokens to toss onto him, such as Mushin No Shin, Shipment from Kaguya or Tennin Institute: The Secrets Within, his returns will be much more agreeable. Overall, he is a safer and less lucrative choice for advance economy than GRNDL Refinery.