If I activate the "Boost" option, how long will my ad stay at the top of the results?
Over time, new ads are created, and appear at the top of the results, making your ad get lower and lower in the list. Other users subscribe to the same option after you and come on top of your ad.
The good news is that you can use the Boost option as many times as you like. Whenever your ad appears less visible or receives fewer contacts, take a Boost option and your ad will go back to the top of the results!