We'll cut to the chase. The typical basic ground-up IFR avionics upgrade is going to approach, if not exceed, $20,000 (in 2015 dollars). This won't buy an autopilot or primary flight display, so you're stuck with steam gauges unless you can spend around $35,000.Sadly, we've witnessed enough buyer remorse over the years when owners upgrade entry-level aircraft for IFR on the cheap. Whether it's an unsupported IFR GPS found on eBay or passing on a PFD that can save money in the long term, it's imperative to price all options before pulling the trigger on the upgrade, including pricing flagship packages.
This is a companion discussion topic for the original entry at https://www.avweb.com/ownership/budget-ifr-upgrades-used-garmin-430w-wins