Re: 500mb
It's a temporary restriction for new accounts for users from countries that are considered "high risk". See Country Restrictions for the list of countries whitelisted (no initial restrictions) and blacklisted (no accounts allowed at all). Countries not on either list are considered "high risk", and have restricted resources at first -- but if you create a site that conforms with the Terms of Service and Acceptable Use Policy, you can have the restrictions lifted after seven days.
Countries are classified by their history of server abuse and illegal activity. It's unfortunate that everyone gets tarred with the same brush, but if there's a fifty-fifty chance (or better) that somebody from your region is going to use the services to break the law or run "greedy" scripts (like proxies), then the host has to minimize the risk. The "high risk" accounts are limited enough that server resources aren't too expensive to take a chance on new accounts, but not so limited that you can't create a reasonable web site. Once you've established that your site is worth taking a bigger risk (and that only takes seven days of good behavior) you can apply to have the restrictions lifted, and will be on the same footing as everybody else.
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