I had an interesting conversation with a well connected dealer friend a few days ago regarding the UK market for RHD Porsche 991 GT3 RS, which suggested that the days of six-figure markups for the latest 911 RS were over and done.

A nice RS had just arrived in stock and was offered to a number of prospects at well below the average market price. Some of his would-be buyers replied with claims of cars being offered behind closed doors for much less than the price my friend offered. Evidence went backwards and forwards until a much lower price was eventually agreed as the RS seller was keen to move on. The seller still cleared the best part of £45k profit out of the deal after paying the dealer’s fixed-price commission.

Average Market Prices for Porsche 991 GT3 RS

Average selling prices for 991 GT3 RS are not easy to calculate without access to accurate transaction data, but the average asking price is pretty straightforward. The premier classified ads site currently has 22 991 GT3 RS models on offer in the UK with prices from £195,000 to £289,995 (22 is not exactly what one might call rare). Average asking price for these cars is a heady £246,000.

This data does not tell the whole story. Amongst these 22 911s are cars with far more than delivery mileage – over 3,000 miles in some cases – and one zero-mileage LHD example. Stripping these cars out and confining data to just RHD cars with fewer than 400 miles on the clock reduces our sample to just twelve cars. Average asking price for these cars jumps to £252,270.

Cost New versus Average Price for 991 GT3 RS

A brand new Porsche 991 GT3 RS bought with no options will set you back £130,296 cost new from Porsche Cars Great Britain, but no one buys a standard RS. A sensible options package of decent paint (£1800), leather trim to the 918 seats (£2k), LED lights (£2k), Front Axle Lift (£2k), PCCB ceramic brakes (£6k), Sport Chrono (£1k) and PCM with Sound Package Plus and phone prep (approx £3k) adds the best part of £20k, which takes the cost new to £149,755.

This £150k list price is for a brand new car with 10 miles or less on delivery, built to your spec and you are the first owner in the log book. The only snag is you cannot order one new: production has been allocated to an oversubscribed list. However, it does indicate what the manufacturer believes their car should be priced at, given the cost to build and their standard margin.

Taking this £150k list price against today’s average UK asking price of £252,270, we see a premium of more than £100k for a car that’s already had one or more owners and may come with up to 400 miles on the clock. If you think that sounds pretty extreme, there is more than one story of a slot on the 991 GT3 RS waiting list being sold for as much as £200k over list at the height of the fever.

Porsche 991 GT3 RS Price Premiums Shrinking

I’ve not driven a 991 GT3 or an RS – these cars simply do not interest me as a driver – but I have looked at plenty up close. The overall impression is of a car that can get away with a £150k price tag, but not a hundred thousand pounds more than that. Lack of supply when the cars were newly-announced sent prices soaring, but now that the RS is two year-old technology and the demand from collectors has likely been satisfied, the low supply premiums are shrinking.

With prices of £190-195k rumoured for cars sold under the radar, that puts the premium closer to £40k for a delivery mileage, one-owner 991 GT3 RS. No doubt some will insist these prices are not happening, but I do trust my source.

Porsche is not building any more 991 GT3 RSs as far as I know, so the chances of these cars – even 10k-mile examples – selling for less than list price in the near future is unlikely, but exactly where over-list premiums will settle is uncertain for now. Will they drop much below £40k? That is entirely possible: premiums usually keep coming down until there is a sudden injection of demand, or supply shrinks as the market soaks up everything available.

Common drivers behind increased demand is a screamingly low price (exchange rate changes for overseas RHD buyers) or a sudden influx of liquidity to the buyer pool, such as city bonuses, pension payouts, capital gains tax breaks or similar. It’s unlikely that a vote against Brexit in this Thursday’s referendum would cause RS prices circa £260k to suddenly look sensible if people are paying less than £200k elsewhere, but there would likely be a lift in demand for sensibly-priced desirable cars like the 991 GT3 RS if economic uncertainty was eased.

Given this prospect, sensible dealers might be considering a reprice right about now. £200k is still £50k profit on list for a well-specced example. Perhaps sellers are not paying attention to the rest of the market, or banking on a big hit to Sterling exchange rates on Thursday. That’s a pretty big gamble if there are only ten buyers out there and they all do deals tomorrow and Wednesday.