Requires heavy computer.knowledge and internet resourcefulness
Get a laptop, load it up with 16gb ram and a 1TB SSD, and spend a day collecting the software for the make of car you're working on. Spend hours building a Windows 7 and win 10 dual boot. Be safe, partition SSd in 100gb chunks, as the software is huge and some won't interact with each other and.you have to install multiple copies of windows, weach on their own.partition.
After all that, it'll do the work of a $5000 dealership computer server
Updated my Ford escapes computers, reset it's entire system and optimized it, and fixed serious issues.
It was neat watching it control everything as it fixed stuff.