Few modern performance estates have achieved cult status quite like Audi's original RS4 Avant. Developed by quattro GmbH and built in conjunction with Cosworth, the B5 RS4 took the already capable S4 and transformed it into one of the defining fast estates of the early 2000s. With flared arches, a twin-turbocharged V6 producing 380bhp from the factory and genuine everyday practicality, it quickly established itself as one of the most desirable performance Audis ever built. SB is thrilled to be listing this example on the platform, finished in Misano Red, and presenting as an enthusiast-owned car that has clearly benefitted from continued investment throughout its life. While showing approximately 139,500 miles from new, the accompanying history file demonstrates consistent maintenance, specialist attention and sensible upgrades, making it an appealing proposition for someone seeking a properly sorted RS4 to enjoy rather than simply admire. Power has been increased courtesy of an MRC remap, supported by a full Milltek exhaust system, with accompanying dyno documentation recording approximately 482PS and 620Nm. Further enhancements include KW coilover suspension, Clubsport-inspired interior additions, Alcantara steering wheel and gear knob, carbon dashboard trim, replacement headlining, repaired instrument display and refinished brake calipers. The service book remains present alongside a substantial collection of invoices documenting specialist maintenance carried out over the years, much of it by respected Audi specialists including MRC and more recently Chapman Auto Services. Recent maintenance includes servicing, new rear brake pads and a replacement battery. For enthusiasts wanting to experience one of Audi's greatest modern classics as it was intended to be driven, this appears to be an honest, well-maintained and highly usable example. As always, the seller is available to answer all questions via the Comments section below and would like to highlight that the personalised Reg plate is included in the sale. Buyers should bid with confidence.