Missions & Complexes

It depends on where you are going and how safe you are. For ninja ratting, a stealth bomber or cloaky nullified T3 (especially the Tengu) is your best bet. For deep within your sov space, anything can work fine (BCs, BSes, HACs, T3s, and Carriers are more or less the best bets though).

In general, without knowing your plans/budget/security of your system, the Tengu is the most general answer I can give you (though it's expensive and isn't always needed).

Before you go purchase the ammo that you want to be dealing, for example if you were killing angel you would want explosive.

What I and most people in the same corp use is a T2 fitted drake, it doesnt cost much and is effective for belt ratting.
For CA we run a few havens and use well tanked BC and BS.

For chain ratting when i first started there was a good little poster i found that helped a lot as it was very simple:


How to chain rats poster

For belt ratting, you can get away with something like 200 hp/s effective tank, while for anomalies, you'll probably want something closer to 300+ depending on the level of anom you're hitting. Speed tanking effectiveness varies on your rats, as well. The other thing you're going to want to look at is how easy you are to kill, and what you're flying. The more expensive your ship, the more of a target you are. People don't like it when someone else rats in their system, and will go to surprising lengths to get rid of you.

The other thing is, of course, that if you aren't in friendly space, you're having to haul out your own ammo. Something like a Tengu chews through ammo at a ridiculous pace, and suddenly you'll be out and having to leave to go restock. Also, unless the system is fully upgraded (and probably has a station installed) or has really good truesec, the money isn't going to be spectacular compared to anything else, even with the recent buff to anomalies. Tank for your rats, and know your triggers, and you shouldn't have much worries aside from pissing off the locals.