Comparison Between Smf and Mybb. Question

[AquaSaberwolf]

Hello friends, We are planning to open a forum site soon. We have decided on the name and hosting. Instead of paid scripts like Vbulletin and Xenforo, we are considering starting with free alternatives such as Smf and Mybb. We have a few questions in mind. Can you help? 1- Smf or Mybb. Which one has more free or paid support and themes? 2- If our project is successful, can we transfer our forum from one of these to the paid vbulletin or Xenforo? 3- Lastly, are there any Wordpress themes that could be an alternative to a forum script? Or do you have any suggestions?