I have become involved in a project to further develop and 
improve the performance of SPECT (Single Photon Emission
Computerized Tomography) imaging.  We will eventually have
to peddle this stuff somewhere, and so as I move this thing
along, I would like to know --

What is the current resolution of SPECT imaging?  What kinds
of jobs is SPECT used for, specifically?  What kind of specific jobs
could I hope
that SPECT could be used for, if its resolution improved,
say, to close to that of PET (Positron Emission Tomography)?
And how much does a SPECT machine cost?  How much does a single
SPECT image cost?  

If anyone knows the answer to any or all of these questions, OR
where I could find that answer, I would be very grateful, indeed.  
Thanks in advance for any replies