G'day, new here and new to guitars.
I have a Yamaha ERB300ii bass and I want a 50w plus amp. I'm just looking at second hand units at the moment because I can't afford something wiz-bang new.
I find getting a something second hand that is not just a good beginner thing is better then getting a brand-new beginners one that I will out grow fast for the same price tag. I've always started off with second hand goods and I like that better.

At the moment I have a free piece of software that makes heaps of different effects using the bass plugged into the Mic on my PC. But I need more bass. And the ability to not need my computer.

So my question is, what features should I look for in an amp? I like playing hard and soft, I want destortion, but I also want to get good sound. I also like to play with plenty of reverb. I'm looking at the 50w - 150w range and only really want to spend upto $350AUD. Been looking in papers and on ebay mostly and I've seen a few in that price tag, so just wanting to know what I'll want in an amp before I buy something that I'll always be wanting more with.

You aren't going to get a good sounding combo, 50 watts or above with distortion and reverb for $350. What you should look for is an amp that suits your volume & tone requirements. Something with a gain control, 3 band eq and volume control, possibly extension speaker out. An Ashdown Five Fifteen is a good example of this.