Is a certain investment in any course good, it really depends on your situation (assuming the course is a good one)
If you have $2M sittinig around your wanting to start buying notes with (or real estate), spending $16k or whatever probable isn't a bad thing,,if you have $25k to invest, then you may want to wait until you have more to invest.
I am always shocked to hear people say (or write), they just spend thousands for a real estate course, but actually they don't have any money to start investing. Read books, read message boards etc while you are building your cash position (assuming cash is needed for notes/buy and hold etc),,,,if your wholesaleing, then it might be a different story, but if you want to "invest' then dont spend all your cash on one course and leave yourself nothing to invest,,,
I'm not saying that education isn't important, it is, but dont' spend all your cash,,save and start your education in a less expensive way