TMR is a class A outfit that would offer you a fair price for selling a used car to a used car dealer....don't go in expecting to get anywhere close to what you want for the sale from an ad. I have gotten quotes from them and Paragon and they were more fair.
Since your concern is the IRS, I will also comment on that. My understanding has been that as long as we use F&F or Zelle then we are immune to getting a 1099. This is how I have operated the past couple years with several transactions buying and selling.