Have to agree with bubbaloo. You get what you pay for, generally.
Having said that I have done renders for very little money to "break" into a client but they always expect the same price and seem to demand more and more all the time. You're better off just to say no thanks, unless you are really keen on just making it a learning experience. If you are good at what you do, the money will come. In my experience anyway.
As far as the images posted, value is difficult. A project that size probably would pay for those type of renders. But I would put a value of at least $1000 for those images.
I do mostly exteriors for large institutional projects that are tied a lot to design development. If I added up my time for some of the renders I have done it would be in the range of $20K - $40 k for some of our larger projects that are between $40M - $50M projects.
The extra renders or sidework, that I used to do, would range from about $1000 - $4000 range for exterior renders, extra views would be very little more as the model is fairly complete and textures are there. Interiors about the same, again multiple views become cheaper as the modeling time is less and materials are worked out.
I am quoting in US$ but live in Canada. The Can$ is pretty close at the moment.
Cheers Peter.