E-Mu SP12 Questions

I’ve recently found a SP-12 in a flea market for an amazing price, the only thing is, its a derelict example. No modern service or overhaul has ever been done to it.
So, I wanted to ask: what are the common failures on these? I know about the battery and the electrolytics (that are more of a universal issue, everything this old that has electrolytics needs them replaced most of the time). But since the issues I know about are quite basic, I want to find out about the specific ones that occur on these machines (mine seems to be an early example, serial no. 411, Paul is the walrus printed on the mainboard, if that makes any difference.)
Also, does anyone know how to 100% determine if it has the turbo upgrade without turning it on? I won’t be able to for a few weeks, and if I have to sell it because of some issue, I want to be able to definitively say that it either has or hasn’t got this upgrade. All of the RAM sockets in the machine are populated and seem to add up to 196kb, which is indicative of this being done. I can also post a high-res image of the ROM chips, if that’s of any help.
Thank you for reading this, I really hope that I can get this E-Mu up and running, I’ve been windowshopping for vintage drum machines and samplers for years now, and I’m really glad to have found this one (especially for the price that I paid for it).

Having all the RAM sockets populated is a good indicator that it is a Turbo. The ROM chips are identical between the turbo and non-turbo units; the turbo mode is unlocked by the presence of an alternate PAL chip labeled “CSMAX” toward the left-hand side of the main board.