I am new to this forum. Currently own a Fiat Coupe and tend to spend 2-3K a year on it, by way of upgrades and replacement parts. So familiar with high running costs, but not as much as RS6

So here is my delimma.. 20K to spend on one of the following with 5k spare for any unexpected expenses
RS6 Plus C5

Audi RS4 Avant B7

In reality is there much difference in RS6 and RS6 plus?
Is there a section where you guys post your cars for sale?
Very hard to focus on the RS4 or RS6 and from all the reading the RS6 plus has everything I need without looking at remaps and custom exhausts.
Lastly, cosmetic question on RS6 C5 rear lights, can i get smoked ones with LEDs?
Either looking now or in a years time..as I love the coupe way too much to part yet..
Thank you for a fantastic forum, as good as Fiat Coupe fccuk.org as far as my experience goes..
Keep it up
Cheers
Nazo