Dealer will probably give you the highest estimate. Take the check and shop it around. You might have a good dealer that does good by you, or you may have a good indie shop that would make the deal a little sweeter.
2014 FLHTCU - "unnamed as of now" 8,000 miles and counting
1997 FLHTC - "Mamma Bear" 150,000+ miles and counting
Here's a link you can check out. You cannot add all the options you might have on your bike. It will at least give you an idea of what your bike is worth. Just click on the year of your bike and then a list to come up of models and click on that. And then the page will come up with some options to add like exhaust but not many options.