TriX Loc: Raleigh, NC

Currently, nice used 5D3s are going for $1500-$1600. I paid about that at a local camera store a couple of years ago, and you should be able to get one from the usual sources for around that price. You want to get one used by an amateur like me who shoots maybe 1000 frames a month rather than one that came from a pro at your local paper that shoots 10x that. There was one on UHH in the last month in that range. You might put up a wanted on UHH (maybe someone buying a MK IV), and check Fred Miranda, your local dealer (if you have one), Craigslist, KEH, etc.

Regarding the 24-105 f4L MKI, they are everywhere in the $450-$600 range since they were included as kit lenses with some 5D series. In fact, one appeared on the UHH buy/sell yesterday. Be aware that there is a known ribbon cable failure issue with some MKIs, but I've been shooting mine for 4 years without issue (but again, I don't shoot every day).

lamontcranston

The 5D MKII you are currently using is capable of producing fantastic images. I'm not sure if the 6D MKII would be a significant upgrade. Take a look at Elena Shumilova's website and see what your 5D MKII is capable of. She produces some of the most beautiful images I have ever seen with a 5D MKII and 2 lenses.

https://www.facebook.com/Elena-Shumilova-Photography-285437411618808/

https://iso.500px.com/interview-elena-shumilova-tells-us-about-her-magical-photos-of-her-family/

robertjerl Loc: Corona, California

But the 6DII is a new generation and when you have Good, Better and Best the next generation of tech often has all three grades being above the three grades of the older tech. So 5DIII is better than the 6D, but the 6DII can be better than the 5DIII, but not up to the level of the 5DIV.

The main question is "Is it the best bang for the buck that does everything I normally do?"

I use the 6D and 7DII. My ideal camera would be a blend of the two. With a higher IQ sensor than both if possible. In the new generation of bodies the 6DII is that blend, the AF system is not as good as the 7DII but it is much better than the 6D and almost as good as the 7DII. Actually the extras are seldom a factor with me since I usually use center point anyway. The 5DIV is definitely better (in most things, however it doesn't have the tilt rear screen the 6DII does), but is it worth the extra money to me???? Maybe, maybe not.

The main slam I have seen of the 6DII is dynamic range. How often do you really need the full dynamic range? Depends on what kind of pictures you take. And as to dynamic range, if it is a stationary subject you just bracket/HDR and the problem is solved. Many people bracket iffy subjects anyway to see what result they like the best. The first rumors of a 7DIII are out, but no specs yet.
Of the two new generation bodies that are out I would still want a combo of the two. The simplest blend I would like is for the 6DII to have the 30mp of the 5DIV. The 6DII AF can do 95%+ of what I would want so I don't really need the 5DIV AF. Not very many people really need the differences in the two AF systems.

Haydon

I realize I'm patronizing my own choices but my 5DIII consistently outperforms me. The biggest step up from the II to the III is the focusing system. I've had it since 2014 and still love mine. Take a look at Elena Shumilova's work. You'll see the aged 5DIII makes images with the best of them.

https://www.flickr.com/photos/75571860@N06/

BebuLamar

Yup it's newer and thus it's an update but it's still a grade below any of the 5D.

TriX Loc: Raleigh, NC

Not endorsing this camera or this seller, but here's an example at $1,699:

http://www.ebay.com/itm/Canon-5D-Mark-III-22-3MP-Digital-SLR-Camera-Body-Only-18-289-Shutter-Count-/272807424101?hash=item3f8496f065:g:zqsAAOSwxk9Zk~MD

Better yet, do you have a good local dealer?

Jakebrake Loc: Broomfield, Colorado

That young lady has more talent than I have ever seen! All I can say is WOW!!!

Jakebrake Loc: Broomfield, Colorado

Thanks for the link TriX. And I have been on ebay as well as CL looking.

mwsilvers Loc: Central New Jersey

What are you hoping to achieve with an upgrade that you can't achieve with the 5D Mark II. Where is the 5D lacking for the subjects you shoot? If you can't delineate exactly why you want to upgrade then I would suggest you don't do it. For certain subjects, like landscapes in good light, you are unlikely to see any significant improvement with the 6D Mark II. The 6D2 has 45 focus points, but they are all clustered towards the center of the frame. The 6D2 dynamic range at low ISO is far from state of the art and is probably not any better than the 5D2. The 6D2 will be better in low light, but so will practically every newer camera. The 6D2 shares a body style with Canon's xxD crop cameras and lacks the professional controls and feel of your 5D2. The dual pixel AF and the articulating touch screen are probably the two most important upgrades, but not everyone will take advantage of them.

boberic Loc: Quiet Corner, Connecticut. Ex long Islander

The same setup, the Pentax K1 and 28-105 can be had for about $500 less. It's a better camera than the 6d 11. Bu if you have an investment in Canon glass forget the K1

LFingar Loc: Claverack, NY

I went from a 6D to a 5DIV, and while I am very happy with the upgrade, the 6DII would have no doubt served me just about as well. Especially since I have a 7DII to cover things like sports and BIF, which were never strong points of the 6D. With the improved auto focus of the 6DII I would think that is less of an issue. You say that the 5DII is getting long in the tooth. Well, so is the 5DIII, even though it is still an excellent camera. My opinion is that if you are going to upgrade, unless a particular camera's spec's or price are way out in left field for your needs or finances, go with the newest technology available. If nothing else, it will just be that much longer before you feel the need to use the phrase "long in the tooth" again and the need to dig into your wallet again.
The 6DII will most likely feel a bit smaller and lighter and it's button placement will be different from what you are used to. The 5DIII would be closer in those respects. Still, relearning those things is not an insurmountable problem. I would also do a comparison of the 5DII and 5DIII to see just what improvements you would be getting. Could be less then you think.

CHG_CANON Loc: the Windy City

Here's a link you should be following if shopping for used high-end Canon gear. The listing changes daily, so you should visit daily, if needed. There's a 5DIII with battery grip listed for $1399. I shoot a 5DIII, but like others, I wonder if you have really outgrown your 5DII. I continue to see wonderful images nearly daily from the 5DII model on 500px. Would your GAS needs be better addressed by a lens? If you need a better focus system and better performance at high(er) ISOs, the 5DIII or it's upgrade 5DIV are the choices superior to the 6D line.

http://www.birdsasart-blog.com/used-photography-gear-for-sale/

Mr Bob

Might be a good time to rent the model you are interested in. After a busy weekend shooting you will have a good idea how best spend your funds.

Jakebrake Loc: Broomfield, Colorado

Yep, I'm heavily invested in Canon glass so changing systems is not feasible.

Jakebrake Loc: Broomfield, Colorado

Thanks for your thoughts, and I'm rethinking about upgrading. Between my 7D MKII and my 5D MKII I have been happy with both. After further research, and eventually coming to the conclusion the 6D MKII wouldn't be much of an upgrade so I think I'll just stay with what I have and resist my gas attack. When I had a 60D I really used and enjoyed the articulating screen, especially for high/low shots, and wish all Canon bodies had them.

Many thanks to all of you for your great advice, and this is what this wonderful forum is all about.