Bitcoin essentially displaces hawala. With hawala there is this set of transactions in two locations which is only possible due to a linkage of trust between the two parties facilitating the "transfer". With bitcoin, a transfer of fiat is simplified into two domestic exchange transactions, independent from each other. One is the buying of bitcoins at one location and the other transaction is cashing out the bitcoins at another.
Ever hawalder essentially can essentially go independent and offer Bitcoin exchange service, ... up to a point.
At most it would mean finding trustworthy people who already have the capital to invest.
The problem is the street-level hawalder agent handling the cash-out needs to quickly turn over the bitcoins received right back into fiat. So the street-level hawalder needs a nearby low-cost exchanger who will buy the hawalders bitcoins and pay out cash.
So there is a capital requirement is essentially for providing exchange service where held is an inventory of cash to be able to buy every bitcoin that the street-level hawalder wishes to sell.
When I see how there are 50,000 M-Pesa agents in Kenya who earn income to supplement their income, (including many who earn so much from it that's all they do), it is a natural that individuals looking to earn a little money by providing bitcoin exchange will figure it out. But what they need help with to get started is a way to turn the bitcoins they bought back into cash.
Down the road this will probably be like a hierarchy. You have the street-level exchangers buying bitcoins and paying maybe 8% below spot. That level may seem a little high but it is necessary due to the time involved to provide this service (arranging and meeting face-to-face is time consuming) and to protect against the risks -- exchange rate risk where the value fluctuates after the exchanger buys the coins after completing a buy from a customer but has not yet sold them. Other risks include receiving counterfeit bills (though with proper training that risk can be lowered) and physical security (i.e., handling cash can be dangerous).
But then if that street exchanger can visit (or get a visit) from a broker-dealer who will convert those bitcoins back to cash at about a 2% to 3% fee then the amount of money earned makes it worth it for the street exchanger to provide the service. The broker-dealer itself might have a trusted party that the coins are flipped to immediately (wholesale, close to spot rate) so that there is no exchange rate risk exposure and exists is a fairly quick method of replenishing the dealer's inventory of cash.
The reason the street-level exchanger doesn't just send the coins to an exchange is because that would involve the banking system, and either the costs or the settlement delays associated with the banking system are prohibitive. And exchange is probably a regulated activity so the street-level exchanger wouldn't use a bank regardless. Even the broker-dealer probably won't use the banking system either.
So essentially, this eventually has tiers like any supply chain. The street-level exchanger buys coins from the public and sells them to a broker-dealer (the next level up in the hierarchy). Then the broker-dealer trades those coins up to a wholesaler (who has the banking relationships and / or relationships with large buyers.)
But this hierarchy isn't necessary to get things started. All that is needed are for the two parties (prospective buyer and prospective seller) to learn that each other exists. These relationships can be learned from attending a local meetup, or from a classified ad on craigslist even.
LocalBitcoins is essentially the closest thing to a hawala network that exists with Bitcoin today as I can (and have) used that to do a three-party transaction. I as the seller contacted the buyer in a far away location. The buyer met with the person who was to receive the cash. That person sent me a text saying the buyer was there with the cash, I released the funds, and the buyer handed over the cash. My recipient of the funds didn't know anything about Bitcoin, except that Bitcoin had made it possible for some person to show up at a certain time and hand over some cash -- no names, no phone numbers, no ID, no nothing. The only technology that was needed at the hand over of the cash was a couple text messages between me and the person receiving the funds.