Recs.
Updated
Brompton is a classic folding bike with 16-inch wheels. It is perfect for everyday commutes, especially when you need to use public transport, because it easily folds into a neat 23''x 22.2''x 10.6''-sized package. The standard build (1 gear, standard suspension, steel frame, no accessories) starts at $1199, but this bike is fully customizable if you are willing to spend more.
Specs
Pros
Pro Perfect for frequent (un)folding and carrying on public transportation
Brompton can be folded and ready for carrying in under 20 seconds, and you don't need any additional tools to do it. When folded, Brompton has one of the smallest dimensions of the 16-inch wheel bikes - only 23'' x 22.2' 'x 10.6'' (H x L x W), making it perfect for commuting when public transport is involved. It's even possible to fit it into an overhead compartment as a carry-on on most airlines.
Cons
Con Expensive, especially when highly customized
Brompton is expensive: even the most basic model starts at $1199. If you decide to upgrade (for example, choose more gears [2, 3 or 6], a firmer suspension, a super-light frame, a telescopic saddle, or other extras), the price can very fast climb up to $3500.