For niche marketing, let's say you found a handful of keywords that you want to write articles for to make MFA sites. However, the keywords aren't related. Is it worth buying a domain for every unrelated keyword or is it just as effective in the SERPS to use 1 catch-all generic domain name for all of the keywords and then simply use subdomains/subfolders to group the keywords?
don't just go for buying domains. just select the main theme keyword form your list and register it with major domain extensions. as the day passes add some content with minor keywords and SE's will grab your site very easily.
You could buy individual domains (depends on the scope of content you are putting in the site and if it makes sense to keep separate), however, we typically advise clients to build one main site, build the content up to be the authority site in the space, and then focus a linking campaign. It also depends on how much time and energy you want to put into the individual sites. Hope this helps. MSG MarketSetGo.com
I would advise you to build content and form a theme keyword for the entire site. That would give return..
I would agree with some of the other replies here keep it as one website and build sub pages around each keyword, make the site look professional and legitimate. By using one website the link juice will be stronger and you will have a better chance of ranking in the search engines for earch keyword.