You can probably best answer your own question by researching boats of sim build/quality to what you are wanting to buy that 10 years ago cost 150k. What are they selling for now? I would guess they are at 75k or lower for all but premium blue water boats that have been meticulously maintained and upgraded over the 10 yr period.
I understand your struggle in trying to justify purchase and determine costs regarding sailboat ownership. All that currently own boats have been thru that, but only you can answer what the value is to you and whether or not you can afford it. Buying any kind of pleasure boat is NOT a good financial decision. If you want to make a good financial decision buy real property that appreciates. If you want to have a blast with family and friends buy a sailboat. If you enjoy "messin about on boats" buy a sailboat. If not, prepare to spend significant sums of money for others to maintain your boat.
I'm not trying to scare you, just trying to be real. If you've never owned a boat before it will cost more than you can ever reasonably estimate. I've owned one for 2+ years now meticulously keeping a spread sheet of maintanence, repairs, amd upgrades and I still can't understand where it all goes. I've yet to have experienced the selling side but have low expectations (although I did buy an older boat that already absorbed it's "new boat" depreciation).
On the other hand if it's in your blood your experiences and time on the water will be priceless.
1982 Islander Bahama 30