At my last 1811 agency we worked with them a lot. I can't speak for the entire agency, but up here in the northeast, they mostly do contract fraud against the DOD such as bid rigging, defective pricing, product substitution, etc... Now that is criminal work, but it is white collar crime, going through documents and doing interviews of folks who tend to be executives of large companies, meaning they have money and lawyers. That means kicking in doors and doing surveillance is few and far between.
They get LEAP and have take-homes. They do go to FLETC bit do not do the IG Academy as an add-on.
I had a case of a military guy stealing stuff my agency provided them and when I went there to ask for help, they were begging the boss to let them get involved in something "juicy." I just needed one body for help getting me some documents. I got 4. And when they found out I was doing a surveillance on the guy, I had 8 agents begging to come along, some who had been on years and never done such. What was going to be a simple surveillance of a package delivery and following where it went turned into a 13 person thing. Many explained they don't get do "this stuff" that much. Nothing wrong with that as they are making million dollar cases, but some wanted to be getting dirty rather than white collar.
Keep in mind the agency mission before you apply for a 1811 gig. If you want to ride a desk, don't like kicking in doors, getting dirty or really only want to work large white collar cases, certain agencies are not the place for you. You have to find what you want to do or enjoy doing and find a agency with a mission that fits that. All to often I hear candidates say "I will take any 1811 gig and worry if I like it later, at least I will be a 1811." Big mistake! You will end up going to a job you will be miserable at every day, something you will not enjoy and end up resent going to work. And that will show in your case work, and thus your performance and thus your rating. Your peers and co-workers will see it. And when you try to leave to agency B, the boss will have agents there call agents they know at your current employer and get the low down on you. And when that gets back to the boss, they will find another candidate. I have seen it happen at least a dozen times in my short time with the feds. Do your homework on a agency. They best place to see what they are really doing is to look at their seem-annual report to Congress.
-In God we trust. All others, put your hands on the car and don't move.