I understand why people are getting frustrated with the used market as it is very slow. However, I was lucky and managed to pick up two 10yr old 737-200Adv in the beginning and since then I have not used the used market at all. In twelve months I managed to get enough cash coming in from my 737's to start placing orders for A320/321s straight away and now have 15 operating and 21 on order, along with two A330-200s.
The 737s have been sent back after a one year lease and now I have perfect fleet commonality and a fleet of brand new Airbuses. The only problem being that I have to wait over 4yrs for delivery of my most recently ordered aircaft
It doesn't particularly matter what planes you pick up in the beginning. If you pick up pretty much anything
, you'll make enough money to get you some orders in with the manufacturers, and get some planes headed your way. Pick up a cheap lease every once in a while between new orders to increase your revenues and keep some orders going to the builders and in very short order, you'll have a constant stream of new planes coming in from the manufacturer. The only downside is that you have to spend the first 12 months or so flying planes that aren't "what you want". But who cares?
If you sit around waiting for a plane that you want on the Used market, you don't make anything. And the order queues for new aircraft get so far ahead of you that you have no chance of realistically getting a plane from one within a reasonable amount of time. The key is to get your orders in the queue early and to keep them going in steadily so that it doesn't matter if they're 2 years long, because you have several deliveries already scheduled throughout that queue and you'll keep putting new ones in, so you get planes every few months at most.
Look at what the biggest airlines in the game are flying. Almost all of them are flying a bunch of cheap crap they picked up on the lease market and a group of new planes that are coming in as a result of the income those 'crap planes' generated. They then slough off the old stuff as they no longer need it, drop their average fleet age rapidly as a result, and increase their image immensely. Thus perpetuating their growth. They don't sit around waiting for that exact plane they want. They take what they can get and quickly grow as a result.
Worry about making money and the planes you want will come as a result of you buying them yourself. They're not going to just get placed in your lap for you.
The point of the game is to make your airline money. Not fly the exact model of plane you want. They're often, in the beginning of the game in particular, conflicting goals.