Missions & Complexes

You can easily make enough isk per month from L4 missions to support two characters so one should be good. Though it is a lot easier to make isk with two characters though.

Doing missions for Caldari Navy is fine considering that they have some pretty good isk/LP items. On the other hand, you do fight a lot of Guristas rights so you're gonna have to deal with jamming a lot. Guristas loot and salvage is ok.

Personally, I don't feel like dealing with jamming so I do missions for the Amarr Navy in the Domain region where the rats are mainly Sansha. The Sansha's tracking disrupting don't do anything to a Raven firing Cruise missiles :). The loot and salvage is better (armor plates FTW!) but the isk/LP items haven't been too great. Barely getting 1000 isk/lp. Then again that's probably due to lazy research on my part.

You don't necessarily have to "train for" a Navy Raven since all the skills you need for the regular Raven is enough for the Navy Raven. The Navy Raven is a good ship to aim for. Also check out the Scorpion Navy Issue as well if the price tag`for the CNR is a bit much for you.

As soon as you can, do incursions. As some have said, you can easily make a plex worth of isk within a 3 to 5 hours. Though, just like missions, it can be a little monotonous. But a plex worth of isk a day is pretty damn good.

As Baljos Arnjak noted, there are other ways to raise isk. Doing a ton of missions can get very boring sometimes. Baljos Arnjak's 50mil estimate isn't too far off: I'm using 5 planets in high-sec, have a pretty crappy PI infrastructure setup, and I sell directly to buy orders. I'm making roughly 60mil a month from PI. So with a little more effort and planning than me, you should be able to make more than me. Maybe 2-4 times more.

As for data-cores, I'm making roughly 36mil to 40 mil per month off datacores from 5 R&D agents. Can easily double that if A) I choose a better corp with better datacore agents and/or B) actually do those once-a-day R&D missions to double my RP for that day.

So those two sources can net you about 100mil a month with not that much effort compared to doing a ton of missions. With that said, once you start doing incursions, no real need for PI or data-core farming.

In addition to the Making Isk Link that Mara Rinn posted earlier, I recommend downloading the ISK 3.0 PDF as well:
http://www.isktheguide.com/

So it's honestly not that hard to make isk in this game to sustain one or two accounts on PLEX alone. Even on just missions alone. Even if you're terribly inefficient at it like I am (see data-cores, PI, and isk/LP mentions)

No. You can run multiple instances of EVE as long as they're all logged in on different accounts. (Can't be logged in on two characters on the same account.)

Just running level 3s in my Prophecy for 2-3 hours and salvaging in my Noctis and selling the salv/loot, I make about 35-50 mil and that's not counting LPs at all, I just bank those. So, my thought is I could sustain myself to play by buying PLEX just doing lvl 3s, so level 4s should be more than enough. But over 60% of that is from loot/salv, and I can loot salv 3-4 missions in less than 15 mins in a Noctis... well worth the 50 mil investment. You make it back in 1 day, even on level 3s. This is in Amarr space, armor plates for the win...

GeForce 8400 with 128MB of RAM does 2 accounts with everything set to minimum.

Haha, that's my problem. I could probably liquidate all my assets and buy quite a few PLEX, but I'm a packrat and I love shopping, I have several fully kitted-out "stations" for my JCs scattered around New Eden - mmmm, new ships, trying out odd fits, shinneeeey!

So for my sins I have to pay a subscription

1. Fit Armor Repairer.
2. Undock.
3. Activate Armor Repairer.
4. Wait.
5. Dock.

You have now saved 20 millions+

- Pantheon Lea

It was said earlier but id just like to repeat it to voice it harder.

You CAN pay account with l4 missioning funded plex it does not meant you HAVE to.

My logic: a ticket to movie theater in my country is like 4-5 euros. Eve sub is 15 euros rounded up. Movies last 1.5 to 2 hours on average. Eve lasts me round 4 hours a day once/twice a week. So the logic is simple. I do both. I play eve cause it its dirt cheap entertainment i like with thrills, nooks, crooks, ship losing, killing and a social side built into the game. Movies are also fun entertainment with pretty much the same arguements except you can get a beer with friends or turn it into a date with someone special.

To me being the slave of "oh gawd must grind plex" is exactly like watching movies alone. Because i CAN doesnt mean i HAVE to nor do i like it.

Now i do see your arguements and i would say that try to figure out if the grind aspect is worth it for you. If yes go for it. Shoot the rats in missions. Make them pay for date drugging The Damsel yet once again. If you dont like the grind shell those few bucks out. The monthly fee in the end might not actually be that bad or even that relevant.

A monthly PLEX doable by doing L4s?

Yes it is. But:
1. It depends on how much spare time you have
2. It depends on the ship you fly and modules you fit
3. It depends on your skills
4. Some social skills also help

Some ships are beter for some areas than others. Noticably Amarr laser ships have limited use against other than EM or Thermal weak opponents. Some ships have a higher max damage output than others. Only Caldari and Minmatar ships have a full range of damage types, making them the most flexible - but Caldari ships often have a big bonus to kinetic damage which actually restricts them. Fortunately the Raven type of ships don't have that restriction.
Also good faction/deadspace modules can greatly increase your survivability and damage output.

Your skills make a lot - if not the most - of difference. A low skilled pilot may not even do 400 DPS while a high skilled one that is able to fit T2 weapons and stuff on the same ship may do over 750 DPS AND will be able to tank a lot more. It's the difference between painfully warping in and out all the time to replenish cap boosters to finishing most missions without even the need to use your repair systems.

Also the social skills increase your LP and ISK rewards which is nice, but you'll usually get the majority of your income from kill bonusses. You could try to mission in lowsec or nulsec but generally it's not recommended as you may lose your ship - unless your alliance controls the area.

Personally the Tengu is my favourite as it's (almost) fool proof, fast and very easy. The damage bonus only applies to kinetic so it's not as effective in Amarr space but next to Guristas, EoM, Gallente (kinetic weak rats), Serpentis, Angels and such are very doable as kinetic is their second weakest resistance.

What salvaging and looting are concerned; I hardly ever do it. Tengus don't have the slots to fit the appropriate modules and getting a salvager from often a lot of jumps away is a bit tedious and more often than not isn't worth the effort, ISK/hour wise. In your case you could train for a Golem.

A general rule of thumb is to not use a BS unless you can fit a full T2 tank on it(made sightly harder on the shield tankers because Shield Management 5 is a pain compared to its armour variant..)

Make sure your active resist modules(the orange things) are pumping out resists that match the damage type you're fighting against. And of course, that they're switched on. You can ignore the shield compensation skills frankly, they don't do **** for your active resistance modules(as you've noticed, they have to be off to receive the skill boost).
Only turn on the shield booster when you need it - trying to perma-run an X-type is always gonna give you major cap issues. Cap management(turning the thing off when you get the chance for example) is considered good practice.

Give this fitting a shot. You already seem to have most of it covered, but give this a whirl. Have a read of the notes placed underneath the fitting for a more general "how to use this" guide.

Finally, I cannot stress enough - you shouldn't be flying a stupidly expensive battleship unless you have a full T2 tank. Weaponry can come later; it's no good having T2 cruise launchers if your tank melts the second it looks at a warp-in beacon. This goes double for faction stuff such as CNR's, Nightmares etc. In fact to begin with, I would recommend focusing your ship mostly around tank. Then as you get more comfortable with its tanking abilities, you can slowly remove tank and replace with gank(the theory being you don't need to tank what isn't there). On a Raven that would be BCU's and target painters... but don't put shield relays in the lows, it'll gimp your cap recharge rate!

I hope this isn't too patronising, and also that I've made some sense here