This way, you are earning $ but, more importantly, not risking anything AND at the same time you are learning what's good, what’s bad (what the professional buyers like or don't like and why) as well as the entire due diligence/backend process so that after you do a few of these transactions, you will be MUCH better prepared to invest in notes for your own account.I've been working with new note investors for 20 + years, matching them up with the right funder depending upon the types of transactions they want to refer.

Is it a bad idea to get a private lender for a long term investment then?

And having something to offer to others isn't a bad idea either (whether it's a deal, connections, etc).Keep in mind, not everyone is going to be successful at your local REIA. 

@Austin Davis I hate to be the bearer of bad news, but whoever told you that “if you have a deal raising the money is no issue” has given you some very bad advice.Raising money from outside investors is always difficult, even if you have a deal, and even if you have a good deal (or even a great one).

Numbers are still not bad if the COCR is strictly on cash.

How much of a margin should I build in to account for bad things happening? 

Ethical HMLs will not lend on bad deals because they don't want to lose their money and they normally don't want your property either.

How many evictions have they handled at the property (may speak to tenant selection quality), how many tenants have left mid-lease (also may speak to the quality of the management, bad managers lose good tenants)? 

I have had excellent success with many Ryobi tools and would not say the brand is bad just because one model I used was not that great.

I also would never want to be in bad debt.