Success Factors For Investing In Property - Paul B.:

Some factors are out of your control, such as
-interest rates
-changes in laws (e.g. Tax law of 1986)
-acts of God

Other factors that can influence your success can be learned, like
-how to do comps
-know how and what improvements to make
-how to find bargains
-property management skills
-what strategy you use in your area

So whether or not it is a good time to sell will depend some on luck, but a lot on skills you can develop.