How to create popular site?

First of all you have to use simple and easy to remember domain (adress). Only latin letters, numbers and - (minus) symbol allowed. Best choise is the name of your region combined with "rent" or "tours" or "vacations" keywords for better positioning of your site within search results in Bing, Google and other search engines. Like this:

http://londonrentals.rentalum.com
http://newyorkrent101.rentalum.com

Bad example:

http://companyname.rentalum.com

Also don't forget you can use your own second level domain with your site. Like this:

http://londonrentals.com (this is paid service which require certain procedures described on separate page)

When filling title, description, keywords for your site use region-related terms (again - it's related to search engines). Good example:

Best vacation rentals in London by Companyname.

Bad example:

Best vacation rentals by Companyname

More technical details available on page "Custom site creation".