When Cap Rates go from 10 to 5 you ?

[Mike S.]

1.) Keep what you have and buy into a 10cap area you see potential in ? 

2.) Buy another rental in the same 5 cap area? (That once was a 10 cap) 

3.) Sell all your properties in the 5 cap area and buy in the 10 cap area

Note: talking multi families/condos buildings only. What I have is 2 Boston fenway Condos and one multi in Cambridge. All went up like mad... rents&appreciation.