It's closer to $60k in most states. The salaries max out at $120k. If you look at the proposal for this money, it's primarily to add agents, not increase salaries.
We also know that it's easy to audit the poor and the middle class. It's really hard and time consuming to audit the rich.
So you are adding agents. You're going to pay them an average of $60k. Agents +/-15 of that average aren't going to be able to audit anyone other than the poor and the middle class.
The more skilled agents will audit the rich, but they will be auditing the work of accountants that don't have to work at the IRS because they actually understand taxes and can make real money in the private sector.
Even if I am wrong, which I'm not, your belief that the rich are cheating on their taxes is wrong. Only .38% of people audited fail the audit. You aren't going to suddenly uncover millions in unrecovered taxes by auditing more people.
You need to do two things ...
1) simply the tax code
2) make those IRS agents, immigration processors and people that help people gain legal citizenship.
2 will get you your tax money, will resolve chaos, and solve your cheap labor problem (which is disgusting, you horrible racist).