Spoletta: There are ongoing investigations in the Trump administration, it is just not being reported that much for some reason. It is believed the FBI obtained a FISC (financial transactions) search order in October 2016 (the initial request made in the summer was narrowed). In addition to this the recent problems for Flynn (the ongoing relevelations he lied about discussing sanctions with the Russians) was brought to light by intelligence sources who moniter communication with the Russian ambassy. It is important to notice that the article in the WAPO on Flynn had 9 (!) separate sources which is unprecedented.
The whole "I got a buisness that can be influenced by foreign governments but but that ain't unconstitutional" thing will eventually be tried in court and according to at least one expert constitutional lawyer it is unconstitutional.
In addition to this someone has dug up a 1929 law that might force Trump to release his tax returns for the past 10 years ;-).
I can give you some generally reliable sources about the ongoing investigations if you are interested.