I think your price expectations are high. I'd expect maybe 50% of the original price. I see GMT Masters for sale in the $6500-8000 range all the time. I assume by Breitling EVO you are talking about the Aeospace EVO. I see them in the $1800-2200 range frequently.
Very few high-end watches hold their value in re-sale. You buy high end watches because you like them, not as an investment.
You can try selling them on beitlingsource.com If nothing else you can look at their sales forum and see what things have sold for over the years. If you try and sell there, use original pictures and be prepared for some to ask you to verify yourself with things like "post a picture with the watch set at 10:27 and a piece of paper with the date and your username."
You can look at ebay for an idea on prices but they are often unrealistically high and many times the watches are fake.
There are other watch seller forums such as Chron24 but I do not know much about them.
If you use online retailers as a guide, remember they price high end and will typically take 15-30% off their posted prices if you call and negotiate.
Good luck.