There is only one camera store about 40 miles from me and they specialize in Canon which makes it hard for me to get hands on with them. Is the 850 really friendly to use? Heard it's hard to get used to because of the large megapixel count and it seems to have a large learning curve?

I am pondering upgrading to the FX line of Nikon cameras. I am on the fence about which to get. I like to take wildlife, landscape, vacation, outdoor portraits and weddings. I have been shooting since the 80's as a hobby and more recently for supplimental income.
I am torn between the D750, D810 and D850. I have the trio of lenses in FX and a few other special lenses all Nikon glass. I even contemplated a D5 which I have found a great deal on a new one never been opened for $4800.
I just need a push in the right direction.

I haven’t made a living from photography for quite a few years. I had an accident where I lost all my equipment and wasn’t insured. Young and dumb. Always wanted to get back into it but I have another profession that pays the bills. I do enjoy photography a lot and would entertain the idea of taking my business to the next level but for now I just do it part time. I also don’t give anything away like some people I have met.
I also thought about getting the D90 repaired but, I feel the need to upgrade somewhat. I do have an equal amount of fx and dx lenses to go either way.

Thank you all for the input. I guess I can’t go wrong on either choice. Just wish I had a few more $$$$ to make choice easier. So if my customers want larger pictures printed I would be better off with a fx.

I am having to upgrade but can't afford the top of the line equipment like D4s, D5 or D850. I shoot weddings, outdoor portraits, landscape and wildlife, sporting events, street and residential home sales and family vacation. I do shoot alot in low light and have a few flashguns and reflectors. I was thinking of going to the D810 or D750 used or refurbed and also toy'ed with the idea of the D500. I can only afford one and all the reviews on the web sites that sell I don't value much the reviews as most seem fake or embellished. I have been shooting digital for 11 years. Prior to that I shot 35mm film. Love the D90 but want to take it to the next level. Also what is the max print size for any of the above camera formats (FX or DX)?

I took this photo black so that I could see what may be causing spots in the pictures. I had the aps-c sensor cleaned but still see these spots in pictures more so when i do night shoots.

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