Buying new parts plus the car will cost far more than just buying an EV from a manufacturer in the first place. That would be if you can even find OEM quality parts for sale to the public. There are many aftermarket EV parts directed towards hobbyists but it is unlikely they are anywhere are robust as what is supplied to the manufacturers. Some of these crate motor plus inverter combos make the same amount of power as an entry level EV while costing 10x the used parts. Batteries can get extremely expensive if you get top quality Li-ion new.
As for the CAN bus issue, it isn't an impossible task if you have the computer skills to solve it. Each device is only sending out a minimal range of data, but the quantity and rate will be large (that is handled by computer). A CAN bus view tool is a must, and then you would have to make an substitute for the device you are trying to replace. You could also fake the sensors connected to the device to replicate the actual sensors, then let the device act as if it was normal. There are some projects out there that have done it but it can be a complex extra step which could be why so many people choose to use an older car.
As for the CAN bus issue, it isn't an impossible task if you have the computer skills to solve it. Each device is only sending out a minimal range of data, but the quantity and rate will be large (that is handled by computer). A CAN bus view tool is a must, and then you would have to make an substitute for the device you are trying to replace. You could also fake the sensors connected to the device to replicate the actual sensors, then let the device act as if it was normal. There are some projects out there that have done it but it can be a complex extra step which could be why so many people choose to use an older car.
