FCP 6 for newest Mac Systems?

Not without hacking the system. Some say use Pacifist, and there was another site that had a solution, but that one is down.

FCP 6 is 8 years old. Old software and latest OS versions rarely hold hands. FCP 7 has issues running on Mavericks (it'll install, but there are problem areas). FCP 6 won't even install unless you hack, and even then, if FCP 7 has issues, FCP 6 surely will too.

I agree with Shaen, use the newest version.

However there is a thread here that explained what to change in the installer. Again, I would not do it: if this is a favourite or necessary application, write off the costs against income.

I think it is not the mac that is the issue but the OS. You have to have a mac that has an OS that runs the FCP6 or 7. I do not remember exactly whether that is Lion or even earlier. Mountain Lion started to be on new MBP end of 2012. So you need an earlier one than that if it must be Lion. Even when a later OS is installed, you can easily go back to the original. When it is SnowLeopard, you have to have a MBP from before "mid 2011".

Adding Ram is dependent on the particular Mac, but in Mactracker (Appstore) you will find how much ram can be installed.

Lex