How bad do I want it? That would be the question for me. I would compare it to items I know I want to use for their functions and see how it adds up. I have spent 79.00 on a pretty but was a bit bummed I did not go for the 'good ones' that I wanted to use.

I have a lot of glass toys because they can be reasonably cheap and are always beautiful! I won't buy a toy that doesn't have an interesting look, even if I think it would function well.

are you going to put it on display? think of what people spend on art. if it's art to you then take that in consideration on the price. hey, there is a collection to start for the curio cabinet

It really depends how much money and space you have. I don't have much of either right now, so I wouldn't buy a dildo as an art piece. I'm unlikely to in the future either - there's a lot of things I find more visually appealing.

Depends on the material and size. If it was something I would already want even if the shape was little more than functional I don't know if I would pay more but I would be more inclined to get it in the first place.