The main machine I have with closed source software gets only one credit card, with a low limit and that is for steam.
I would be setting up VM for this. More likely I would just call and get what I need or switch carriers.
I didn't use a second. I don't want to deal with the hassle. I don't want to have someone steal tiny amounts of money.
Perhaps, I have other things than financials that are sensitive on my machines.