Welcome to the forum!
I use Postimage, too. It's free, but it doesn't have some of the features that subscription sites do. You can't sort your images, for example, though that might not matter. Also, the owners have a habit of letting their account with their own host lapse, and then falling prey to site kidnappers, who snap up the domain name and ransom it. That has happened twice. The impact on us customers is that some of their URLs wind up changing, breaking the link for images you have posted elsewhere.
I'll second GM on Photobucket. They were great, with a good free account, and reasonable rates for more storage beyond what they offered free users. Then they decided to make up revenue by dropping the free account, and offering linking your images only for $499 a year. You could store images for less, but they wouldn't be linked. So the broken Photobucket links you see are from those customers whom they jettisoned. They've since walked that back, offering accounts like they did before, but I don't think anyone who was a PB customer then, has gone back to them.
Anyway, I look forward to seeing your builds!
Best regards,
Brad