HELP NEEDED!!

There are only 3 cars...with 1 of them really close to the drop-off point (you can jump up on the surrounding ledge to get to the car quicker on foot, rather than circling all the way around across from the stadium). There's even a Blista van that spawns inside the garage opposite of the Pay&Spray to get in and go after one with. BTW the drop-off garage is right near the P&S, so you don't need to worry about damage (in general)...just put the pedal down and hit the P&S before delivery.
So grab the Liberty Tree car first (so you don't need to backtrack to this end), then the stadium one, then the one at Ft.Carson hospital.




I dunno what you mean by I/E "missions". You can deliver the cars at any time, before or after finishing the storyline. You can even deliver required vehicles before areas are unlocked. The only one that will not spawn in Portland for the Portland garage under any circumstances is the Dodo (use either of the glitches** to get one early and fly it over the broken section of Callahan bridge). By contrast, the I/E in Shoreside can be completed fairly quickly using the glitch (because the tunnel is not blocked from Staunton early in the game). The only problem one is the BF Injection there...which normally does not appear until you kill Salvatore (but you can use a firetruck mission to try to get one early).

The first 4 emergency mission vehicles can be collected in Portland for the crane. You pretty much HAVE to wait for the FBI Karuma and Rhino, as you cannot aquire enough stars until you've unlocked areas. Tho it's true that you can just use a Rhino spawn code to get that one (no penalty for using cheats in III), you can also get one early in Staunton in the mission you have to protect Phil in (push it to the safehouse garage, and it's yours).




** Ways to get to locked islands early:
The obvious way is to use the code that lets cars fly like Dodos, and just coast across the gap in the bridge. However, there are 2 other ways to get over there without cheating.

The first is to jump (on foot) from the broken girder that hangs below the bridge on it's North side, to the other broken girder. Then just run up the girder and onto the other side of the bridge.

The other way is to park an ambulance on either sidewalk just inside the tunnel. After driving down to the blue barrier, it's quite easy to spin around and back up onto the sidewalk. By jumping up onto the ambulance, it's tall enough to allow you to poke your upper body through the ceiling. You will be stuck in place, but trying to jump toward the center of the tunnel will make you fall up onto the top of the tunnel. Then just run over to the Staunton coast and jump off the tunnel into blue hell. You will respawn on dry land at a cost of 5 points health or armor.

In either case, the tunnel will not be blocked between Staunton and Shoreside (the barrier is occupied blocking Portland).