[Nemo]

For our team, it was a multi-year process to build our way to two sets of electronics, and it has been an ongoing process as we buy more expensive stuff to replace components that are obsolete or fried.

The first thing I'd want two of is the power distribution board so I don't have to wire all of the motors at the event. Next after that would be motor controllers, but those are pricey.

Take advantage of FIRST Choice and vouchers to build up your supply of DC motor controllers from year to year. Rob last year's robot and reuse those. Purchase a couple extra every year. You can mix and match and choose the less expensive ones (Sparks via cash, Victors via Vex voucher and FIRST Choice).

It's easier to move just the RoboRio and VRM than it is to install a full set of electronics. Since the RoboRio is a lightweight $400 COTS component, it makes economic sense to withhold that piece for use on your practice bot.

A practice bot with partial functionality can still be quite useful. Just having a chassis with rolling wheels on it can be enough to do some manipulator development and testing. Or a driveable bot without any manipulators can be used for some autonomous motion testing.

It's better to have a completely identical practice bot with a complete set of spare electronics, but there are some useful intermediate setups on the way to having the full set.