We're wanting to purchase a few URL's that have the keywords in the URL that we want to rank for. We will have these URL's directed to our main website.
I'm trying to find out what would be the best choice for a URL.
I want to rank for both Boat Ladders and Boat Ladder.
Which URL would I choose? - BoatLadderNow.com or BoatLaddersNow.com (One is plural the other is not)
Would one URL be better than another?

Also, would it be better to have a word before boatladders.com; for example "MyBoatLadders.com" or better to have the word after; for example "BoatLaddersNow.com"?

Hope my questions are clear, please let me know if I can clear this up at all.
Thanks for your help in advance.