It seems that 200-250 is the average price for spaying in Miami.
As per the health insurance, my friend has VIP Insurance, it covers 80% of the spaying costs if i am not mistaken...u have to pay in full and they will reemburse you, i think it comes out about 10-20 dollars a month...
Ohh, and please please do blood work, i have seen a case that a schnauzer had a problem in her blood (her blood wouldn;t coagulate {sp??}) So just to be on the safe side, i highly recomend that!!