I have about $2000 (US) available to spend on a 3d program that will give me very realistic renders of human figures.  I will only use the progarm to make static renders.  I am not interested in animation or modelling.

I am proficient with Poser 6, and have a huge library of DAZ and renderosity figures.  I intend to use these figures in my renders.  Ergo, the easier it is for me to import my posed Poser figures to the upper level rendering program, the better.

Which one would you advise?  Thank you.

 Well , just get Vue. The current vue is 7.5 and about 900 dollars.

It would make no sense to buy a full Modeling program if you're  not going to model.

Or lightwave for around $800 or so.

Attached Link: http://www.runtimedna.com/Poser-Render-Studio-For-Vue-6.html

Check the link.

Vue 7 Infinite
or Lightwave
or Maxwell Renderer (But, getting Poser folk to work in maxwell studio will take a lot of work!)

check my gallery for Maxwell (model work) and Vue renders (scenes though I don't go for photo realism, I heavily stylize my scenes in photoshop)

or better yet, but Vue 7,5 Xstream and Lightwave and you can do everything!! ;)

(note, for Vue, it works best on a 64 bit  PC, but any 64 bit app will work better on a good rig, since you can use a hell of a sight more Poser folk when you have 8 gigs of RAM or more!)

Vue all the way.
But as Geep shared with some other programs and understanding what diffuse,bump and specular channels do you can get some decent renders out of Poser...tweaking the lights too!

Another vote for Vue here too!

I Would have to  say or DAZ studio Advanced

Quote - Which one would you advise ?

Try whatever free apps you can find, and any demo versions of paid apps in the hopes of finding something that you can get along with.

Also keep your eyes open for sidegrade offers and (upgradable) magazine cover disc freebies.

It's not as expensive, but there's always DAZ's Carrara Pro too. It's render engine is pretty good, and it is Poser friendly too (as much as any of the others mentioned) and able to load content from a Runtime inside the program.

Vue is my personal weapon of choice, but I've also seen some stunning work done with C4D. With the InterPoser plugin, importing Poser scenes should be a snap.

Get both Vue 7.5 Infinite and Shade 9 Professional. Both have PoserFusion capabilities. Vue has some support for importing Shade native files, though Ive heard it will be updated soon, too.

If you aren't sure about Shade, then get Shade 8.5 Standard Edition for free in issue #3 of 3D Artist Magazine, out now.

There are a few options I'd recommend. First is Lightwave, which is a nice piece of software and not too expensive. It has a lot of flexibility, is used in professional FX houses, and with the Poser Pro scene hosting can load in Poser scenes. It's lighting capabilities are far better than Poser's. Lots of online support exists for Lightwave and the render engine is fast.

The other option is Cinema 4D, with Interposer Pro, which will allow you to load in and manipulate Poser objects within C4D. It has some nice render capabilities--again, far better than Poser's and it is a pro-level program. They also have a crossgrade sale which allows you to pick up their program for 50% off if you already own a qualifying program. The render engine is quite quick as well and it would be tough to judge whether Lightwave or C4D would be faster.

I've used Vue, but the render engine can be painfully slow and if you're looking at doing human renders, then you may get equivalent results much faster using the two programs I've mentioned above. Vue is best for landscape renders and stills, not so good for animations unless you have a lot of time on your hands.

Now, whether you're doing animations or stills, I would suggest that you look at render speed as one of your factors in choosing your 3D app. You can get a lot more art done if the renders take seconds per image as opposed to minutes or hours per image. To put it in perspective, I've had renders in Lightwave take less than 30 seconds per frame, while equivalent renders in Poser would take 3-4 minutes per frame. An equivalent render in Vue would probably fall inbetween the two in terms of time, but I have had some Vue renders take hours per frame especially if you've cranked the texture filtering up.

You can also look at Maya and 3DS Max, but I think those are beyond your budget. I don't use either so I can't comment except to say that they have a lot of users, and a lot of support--definitely the "big two" of 3D animation software. You can also look at Softimage XSI, which I think would fall into your budget range, but not having used it, I can't really say much about it.

Definitely try out the demos. If you're going to be dropping serious cash on a 3D app, you'll want to make sure that it fits for you.

Softimage XSI's main strength is animation, so that might not be the best solution for the OP.
3DS Max and Maya - well, those are the high end all-in-one packages, modeling, rigging, animation and rendering are all at a high level.
I've seen some examples of the hair plugin "Shave and a haircut", and those are damn impressive. But also highly expensive.
Same goes for the plugin renderers - great quality, at a great (as in a great amount of money) price.

As far as hosting scenes goes, I've tried the Poser Pro plugin for 3DS Max, and I was extremely NOT impressed. Not stable, dynamic hair didn't come across, limited scene complexity - if I were to render in Max, I'd prefer the Collada or OBJ route.
I do not know if the hosting plugins for Lightwave or Maya are any better.

What I do know is that importing Poser scenes in Vue is painless - and that includes dynamic cloth and dynamic hair. The render quality of dynamic hair in Vue is mediocre at best, Carrara does better.

I echo that the best option is to download the trials and see which one works best for you.

I'm partial to Cinema 4D with the InterPoser plugin (Kuroyumes), but I'm more of a hobbiest and needed something that I don't have to relearn when I don't get to it for a few months.

Posermocap
Vue7 has a much faster Radiosity / GI render engine, now, fyi :)

If all you want to do is render static scenes, this is definitely an option. You can bring your posed Poser scene into Modo, including clothing and even dynamic hair (sort of) throught the "Point cloud" approach. The render engine and lighting are excellent.

Attached image used Poser mesh for the figure, brought into Modo and further sculped, with the rest of the scene assembled around it, then Modo lighting and render.

I think you should post a render by you or anyone that shows the kind of work you wish to achieve.

::::: Opera :::::