Brompton's annual price increase is fairly consistent, about 2% above inflation and kicking-in around end of the year. I didn't need my next Brompton til about April but I ordered in late October to be sure of getting the 2011 prices. I priced out my spec and it is now 6% higher in 2012 prices, which is less than I thought as UK inflation has been 5%.
I've kept my invoices from 2003 for all my 4 Bromptons and my 2007 one for example is a M6R-X and it cost me
The same 2012 price is 700+120+500+10+30+100+15+20+25=1520 so a 55% increase from 2007 prices, an average of 9.1%/pa.
Units Items Price Total
1 Brompton M-Type GBP 500.00 GBP 500.00
1 Fit 6 speed standard gearing GBP 60.00 GBP 60.00
1 Tempest Blue Titanium frame GBP 315.00 GBP 315.00
1 Fit rack and guards GBP 37.00 GBP 37.00
1 Fit Easy-Wheels GBP 12.00 GBP 12.00
1 Fit Standard Steel seat pillar GBP 0.00 GBP 0.00
1 Fit standard foam saddle GBP 0.00 GBP 0.00
1 Fit Marathon Reflex tyres GBP 12.00 GBP 12.00
1 Fit front carrier block only GBP 15.00 GBP 15.00
1 Fit battery light set GBP 35.00 GBP 35.00
1 Cover and saddle bag GBP 20.00 GBP 20.00
1 Do not fit folding pedal Not Recommended GBP 0.00 GBP 0.00
1 Fit Dual pivot front and rear caliper GBP 5.00 GBP 5.00
The $/Sterling exchange rate throughout all of 2011 had a max/min of
$1.67070/$1.53440 and yet their 2012 exchange rate is 1.62 which is a little above-average, plus UK prices include salestax and US prices do not. That adds up to most USA paying >10% than UK.
So tough! If you wanted a cheap Brompton go back in time and buy in UK, you'd earn more interest than money in bank over same period.
I'm possibly selling a Brompton, its makes most sense to store it dry and wait til I need the space or cash and then sell. My 2003 Brompton I squirted with anti-rust stuff and stored it at my mom's house and used it when I visited, I reckoned I'd not use it for a while so in my last viisit I sold it, and sold it for what I paid for it in 2003. My 2006 and 2007 purchases, I deliberately bought Ti because quality keeps value, and Ti now is very hard to get and almost double the cost.
I also can move my parts between my Bromptons, I'm moving wheels and lights between two Bromptons to get the specification how I like, and this last year I've moved parts around to make the type of bike I need, e.g. I was commuting in bay area for 4 months and made a S6L-X which is fast flat & windy configuration and shortly it will get a replacement hub and its hub end up on a steel frame for a mountain touring bike.
Can you imagine the problems Dahon buyers get, they wince at the cost of Bromptons, buy a lower-cost bike and lose most of their money when they sell it and much less interchangeability of custom parts.