1. i think you're limiting yourself. i have a 20" wheeled dahon that i've never locked up. i bring it with me almost everywhere. most people do not mind - i think they are sometimes too fascinated by it to remember their policies. lol. a brompton is even smaller and has a more compact, less conspicuous fold. rolling it around folded shouldn't be a problem in most places. i'm in l.a.

2. i would not lock up a $1500 brompton outside. that's just me and that's partially why i don't think i'd want one. i'd constantly worry. i imagine people who steal bikes for a living know how much bikes cost. if i was a bike thief and saw it outside of your class, i'd know you probably have it there all the time, giving me an opportunity to plan my theft. good thieves do scout your crap and watch your patterns and habits.

3. if you're really that concerned about your bike being stolen, get a lower-priced bike. i've had a dahon for a year, ridden just about every day with no problems. it doesn't have the cache or snob appeal as a brompton but they are still very good bikes (50 models or so) that comes in a range of quality and price points.

i once saw a guy in the subway in l.a. with a brompton. he looked like he was guarding that thing with his life. he looked so afraid someone would rip it from his little hands. i don't wanna live like that. i recently test road a brompton and just couldn't find a reason to pay that much for a little foldie. i once saw a bike friday locked up outside of a whole foods but it was black, beaten up, and could have been stock - under $1000 value. it wasn't that attention-grabbing.

so for me, if you think you'll be gutted if it's stolen or don't feel comfortable wheeling it around with you, it may not be the bike for you. just sayin.