On this listener Q&A episode of the Dentist Money™ Show, Ryan and Matt answer a couple of common end-of-year retirement plan questions. And, after watching some U.S. markets reach all-time highs, are you wondering if it’s still a good time to make a lump sum investment? “Backdoor” Roth IRA’s can be effective, but there can be a few complications you should know about. Plus, when putting retirement funds into an extra entity you’ve set up, the IRS has some rules you definitely need to know.