The first and foremost cost while building a website is the domain name. The price of the domain name depends on the TLD of the domain which you are choosing. For an example the price for a.com TLD ranges between $9 - $13. The price depends upon the registrar from whom the domain name is purchased.
The second major cost while building a website is of web hosting. A web hosting may range from $1 a month to $100 a month depending upon the purpose for which you are taking the hosing. For example if the website is a simple blog website or a business website then a webhosting of $1 per month is sufficient enough to support your website however if you are thinking of an e-commerce website, then a webhosting having its price as $100 should be the right solution. Also the price as $100 is not enough to justify your shopping for hosting. Secured servers, high traffic capacity and 100% uptime is what, is the need of the hour when choosing the web hosting.
Now this is where the actual cost of the website depends. While going in for special templates using a CMS platform like wordpress, one can have it for free but if the programming language of the website is in HTML then hiring a developer expert in HTML will be the only solution. For designing a template your developer may charge somewhere about $200 to $1000 depending upon the work. This category may also include the price for a payment gateway too.
So a combination of all the three points mentioned above becomes the formula for calculating, how much it costs to make a website. We have often seen that when we want to have a website built, we call up various website designers and ask for quotations from them but the issues come when one needs to finalize the website building company based on the quotation.