posted 11-13-2011 12:26 PM ET (US)
Any fairly recent boat and engine, that is still in production and available new, has to be priced against what a brand new 170 will cost, including shipping and sales tax, plus the values of extras that you have added that may add value (some won't unless they are parted out).So that's where I would begain, finding the best local deal you can on a brand new 170. Any would be buyer will definitely check out "going new". I would say yours might be able to bring 75% of that cost, maximum. No bottom paint is a definite plus for most, but not all, buyers.
You are disadvantaged by the earlier, lower center console, but many buyers may not know that, or may not be too tall!
Unfortunately, the 115 one year old engine won't add much value in comparison to a new 90. 4 MPH in top speed (or whatever it is over the Merc 90) won't change the 75% factor in my opinion. Being 25% overpowered could actually hurt.
Then, once you have that 75% value, or whatever fraction you want to use, check the national used market. You will have to compete with similar condition used boats also. They may force you to adjust value down to more like 2/3 of price of a new one.
It may sound crazy, but if you really want to sell the boat, selling the engine separately may return more of your investment. Buckda had to do that recently. An un-powered 170 may have good appeal to a buyer that does not like Mercury.
Did you ever tell how how well this engine ran against the similar Mercury 115 ProXS?