How much should a part-timer charge?

What do you think someone should charge for a 300-500 word blog post? I've seen a few articles about this online, but they're all talking about someone who wants to make a living freelancing, whereas I'm only going to be doing it part-time. I'd have to do some research on the topics (DIY, cooking etc) but the amount of time it takes varies from post to post so it's kind of hard to estimate an hourly rate. I've seen some say 10 cents a word ($30 a post) is fine while others say it should be about 50 cents per word (about $150) or more...what's correct?

I do have a five years of experience, but I know I wasn't being paid a good rate before.

Thanks!

How much should a part-timer charge?