How do you buy individual commentaries instead of a whole set?
Unfortunately, many commentaries are only available in sets. Did you have a specific one in mind?
I preach through books of the Bible and I always buy the NIV application commentary and MacArthur. Is there a way to transfer a kindle version?
No, transfers from other book libraries is not possible. Even if the Logos software were capable of some sort of third-party book import (which it isn't), it wouldn't be possible to import Kindle books anyway because they are locked down with DRM from Amazon so other readers are not able to read Kindle books.
I preach through books of the Bible and I always buy the NIV application commentary and MacArthur
MacArthur commentaries are available individually (just search on logos.com for them), but NIV application commentaries are currently available only as a set.
This is disappointing to find out. I have been slowly collecting the best 2 or 3 commentaries on each book of the Bible as hardback books. The best commentaries are not in any set. I was just thinking I should change from getting physical commentaries and get them, as I can, in Logos. But from what you say that won't work in most cases.
Logos tend to split sets only after a couple of years. So it won't work for newer sets, but it might work for some sets that have been around for a long time. In some cases, the sets offer such good value for money (the Tyndale and BST sets are good examples) that it's worth buying the whole set even if you only want a third of the volumes.
I wonder why it is done this way. If the publisher is requiring it, it seems they are only hurting themselves. I wouldn't think technology is the reason. I've been a software engineer for over 20 years and would think that things would be developed so that new books (commentaries) would be added so that they could go either in sets or as individuals by default.
In seminary several of my professors discouraged getting whole sets simply because the way to get the best commentaries was to pick and choose. They even published an annotated bibliography to indicate which were the best ones. As you mentioned, there are some good ones in the BST series and it isn't so far out of range. But getting the entire Interpretation or NICOT and NICNT series would be beyond most pastor's budgets. I hope individuals are available much sooner than two years out.