Blended rate on $285k mortgage of say 8% is $210 per unit.

Have a client going through them on one time construction loan for a new build and I have had clients use them on a Cross Collateral Loan where people can buy a home without a contingency on selling first (hard to get accepted offers on contingencies in Boise these days) as long as the blended LTV of the two is about 75%.

Sometimes you can find a nice blend of both, but often more of one than the other. 

It might not be "fun" but taking a 4% return on Property #1 knowing that it will enable you to raise a blended average return over time it's exactly bad!  

Jeff will also say that you should know REI from a fix and flip or LL vantage before investing in notes (Jeff, forgive me if I'm incorrect and excoriate as required....I never want to put words in others mouths) but, if you can evaluate the underlying collateral accurately, and are willing to learn about notes and buying notes at a discount, then REI note investing may be the perfect blend between stock market-ish and REI returns that fit your lifestyle and goals. 

That said, even with a higher rate, it may still be more beneficial to go this route than a refi when you consider your blended rate.

Need to blend this all together.

The difference between a fund and a one-off investment like we do, is the funds/returns can be blended between deals, if you invest in a fund you may not know the specific properties that will be acquired, and it's just less known.

Also, I don't think most people like the aesthetic look of them, maybe someone can develop a solar shingle so it can blend in with the house better haha.

I like going for a blend.