Good advice .... I think it's also important to make sure the product is one you are proud to show, want to share and feel like is reasonably priced. I can't imagine trying to sell something that you didn't want to wear, use, show off ... I think it is essential to be sure you love your product.
I think training is also an important feature and saturation of the market. There are home party plans out there that everyone has heard of, everyone has been to before and some of those might be seen as a little "tired". That's really unfortunate, because they may have some superior products, but, there it is!
I like that my company is unique ... no one else is doing anything like it. That might be something to consider.
One other thing to consider might be whether you're interested in a consumable product (cosmetics, food) or non-consumable (jewelry

, kitchenware). While consumables can generate a lot of repeat business, you might also need to maintain inventory in order to properly service customers. I've used cosmetics before and it was really frustrating to have to wait for my consultant to order it.
You might also consider whether the company has an online presence ... ability to order online and still receive consultant commissions and stuff like that.
That's my SHORT list

!
Ginger