The site is based on OsCommerce which is free so you would be paying for the information/contacts and the domain until October.
It also looks as though it could be quite time and outlay intensive. You will either have to stock everything that is on the site or order it in on demand. If you do that you won't get very good bulk purchase discounts and you will keep your customers waiting.
You can get lists of wholesalers at a newsagent and you could buy a domain of your own. You would have to set up OsCommerce but there are a couple of us who can help with that and it has a thriving support forum.
Personally I wouldn't go for it but others might disagree - I might be missing something.
I've just spotted that the site shown in the advert doesn't look like the site that is linked too - the name is different too. There is a lot more listed on the advert screenshot. (Not that that makes much difference - you would have to change the catalogue to reflect what you decided to sell anyway.)