To the right end user you can MAYBE get $500 but that aside, just based on the domain name alone it isn't really worth all that much.
If however the domain name has other value such as a large number of backlinks, age, traffic, content, etc. then you start to build up additional value.
The problem with using those automated services is that you have a common word like "sweet" in the domain name and it can sometimes confuse the systems that value domain names. Same thing tends to happen when you have other common words like "online" or "my" in them.
Anyway, good luck
