Before you book your next trip you may want to identify how easy or difficult it is to acquire the materials required upon arrival. For instance, some countries like Australia allow you to obtain the necessary visa for visiting directly off the internet in virtually no time at all. Still, there are others that can keep you holding on for the approval for weeks, or even months at a time. One thing you should positively do, even if you are familiar with a countries prior practice regarding visas is contact the embassy. Sure, you may have gotten things done in a snap three years ago, but things change dear travellers.
In addition, there can be fees that you are responsible for upon your arrival to your destination. If you are working with a tight budget this may become an unpleasant surprise, if you were not expecting to have to shell out anything just to enter the country. Some places only ask for a nominal fee, but others are weightier.
Also, there are some countries that have requirements that you would never imagine, if you had not inquired of the proper sources. An example of this is Russia, where you must be invited by letter to visit. Yes, we all like to believe that we are special, and that we will be welcomed with open arms, but if we do not follow the rules we may find that we are in a bit of a jam after a very lengthy journey.