Since I've been trained properly on the nuances of TNRM.  Specifically trapping, it's not too bad.  If anyone has the time and commitment to assist, traps can be loaned so that part of the cost variable to minimized.  Neutering does is an expense and hence the reason for the voucher recommendation.  A few programs (volunteers) are currently in place to provide a low cost neutering procedure.  Regarding knowing which have been neutered...it's a notch on the ear (left for males and right for females).  Hence, you take in the one's who have not been neutered and release those who are.  Again, it takes time and commitment.  I know there are those who are responsible, but that goes for almost everything...we just got to try and take care of our own corner of our Community.  Sadly there are those who will not listen and collaborate on a reasonable human(e) recommendation to an ongoing issue.