Yes, I've run into this situation as well. I've found that I need to comparison shop a few times. After a while, you will start to see patterns. Drugs A and B might be best through Part D. Drugs C and D best with SingleCare. Drug E with GoodRx.
Specific pharmacies' prices might also vary widely within each "insurance" vehicle. For example: With SingleCare, Walgreens might be cheaper than CVS for one drug but another drug might be cheaper at CVS than Walgreens.
Also, be extra vigilant when there are supply shortages. The lowest price won't help if the drug is out of stock.
Mom
Totally get your challenge. As one who is trying to figure out how the drug industry gets by doing what they do. My Part D is only available through six plans and four do not include one medication in their Formulary.
Went and talked to the pharmacy and druggist. She suggested what you are doing. When the insurance works use it and when Good RX or she has some other organization I never heard of, use them (pharmacist will furnish me the coupon at time of sale). As you know using other programs means the drug cannot be run through insurance.
Got a shock the other day. We are not allowed to change drug plans in the off sign up times of the year but, the drug plan can CHANGE their Formulary and add or remove drugs anytime they choose.
My one little bottle of special eye drops is $408 a month. No laugh when I hear of Seniors debating food or drugs! There are other meds I take but this sticks recently in my mind. Really ticks me off that other countries pay much less!!! 
I was recently diagnosed with something, errr, something not good, but if managed properly, something else will probably kill me first. Regarding that "managed" part, I had two options, 1) monthly expensive injections, or 2) a many times more expensive 1-time surgery; I opted for the latter. Yeah, the surgery cost over $4,300 out of pocket (my insurance covered most of the bill), but I figure I'll come out ahead in less than a year, and my plan is to stick around for another 20 or 30 years. 
This getting old stuff stinks. 
@Horseshoez wrote:I was recently diagnosed with something, errr, something not good, but if managed properly, something else will probably kill me first. Regarding that "managed" part, I had two options, 1) monthly expensive injections, or 2) a many times more expensive 1-time surgery; I opted for the latter. Yeah, the surgery cost over $4,300 out of pocket (my insurance covered most of the bill), but I figure I'll come out ahead in less than a year, and my plan is to stick around for another 20 or 30 years.
This getting old stuff stinks. :smileymad
yes getting old stinks . I hope you on the road to a full recovery .
@Jnbmom wrote:
@Horseshoez wrote:I was recently diagnosed with something, errr, something not good, but if managed properly, something else will probably kill me first. Regarding that "managed" part, I had two options, 1) monthly expensive injections, or 2) a many times more expensive 1-time surgery; I opted for the latter. Yeah, the surgery cost over $4,300 out of pocket (my insurance covered most of the bill), but I figure I'll come out ahead in less than a year, and my plan is to stick around for another 20 or 30 years.
This getting old stuff stinks. :smileymad
yes getting old stinks . I hope you on the road to a full recovery .
I had forgotten about this thread; I have an update...
My doctor has me on an additional medication, and I almost choked when I heard about the cost, it is a single tablet per day at the cost of $100 per tablet! Fortunately I qualify for a few programs which help offset that cost.
@Horseshoez wrote:
@Jnbmom wrote:
@Horseshoez wrote:I was recently diagnosed with something, errr, something not good, but if managed properly, something else will probably kill me first. Regarding that "managed" part, I had two options, 1) monthly expensive injections, or 2) a many times more expensive 1-time surgery; I opted for the latter. Yeah, the surgery cost over $4,300 out of pocket (my insurance covered most of the bill), but I figure I'll come out ahead in less than a year, and my plan is to stick around for another 20 or 30 years.
This getting old stuff stinks. :smileymad
yes getting old stinks . I hope you on the road to a full recovery .
I had forgotten about this thread; I have an update...
My doctor has me on an additional medication, and I almost choked when I heard about the cost, it is a single tablet per day at the cost of $100 per tablet! Fortunately I qualify for a few programs which help offset that cost.
Best wishes for a good outcome to @Horseshoez .
I just got confirmation of shipment for one of my 90-day mail order prescriptions. In January, that medicine cost me almost $800. Today, my bill was only $60 due to some coupon that the PBM applied on my behalf. It's hard to believe, but they lowered my cost without me having to proactively ask for any discount. I wonder what the price will be in 3 months?