I wouldn't use rhel if I was you, except if your a developer, it mostly is an enterprise product only, has the licensing is just too troublesome for anyone not making a professional use.
Giving a contribution (mostly your time) to one of the project they support would be a better idea if you ask me. (It not like they themselves need a tip from regular user, they are the biggest business based exclusively around Linux after all)
Has for the memory basic desktop license is limited to 8GB, workstation license is unlimited from their datasheet.
Link to the datasheet pdf.