"What are your hard limits?"
This one is easy: needle play. I cannot stand looking at needles, being around needles, or thinking about needles. Just writing out that sentence about needles made me start to feel like I have to throw up.
And I would never allow a third person into our sex life, neither man nor woman. Going to shows, watching scenes, being a spectator--that's one thing. Allowing someone else to touch me, or my husband, sexually for the purpose of intercourse, that would not be okay. Not that this has ever been an issue. My husband cannot stand the idea of another man even touching me, unless it's a polite kiss on the cheek.
Everything else, at least everything else I can think of, I'd be willing to try at least once. We've never tried anything like cosplay or pony play, because we have absolutely no desire to. But if my husband suddenly decided he wanted to dress up like Han Solo and put me in a Princess Leia slave dress, I wouldn't mind. We're both pretty open minded about trying out new scenes and new toys.
What usually holds us back is not apprehension or some kind of 'hard limit,' but cost. Like the bed I want so badly: it costs close to $4,000. There's no way we would spend that kind of money on a kinky piece of furniture. A flogger can cost upwards of $400.00; even good suspension cuffs can cost over a hundred bucks. We have three kids; we don't spend that sort of money on ourselves.
Although, our wedding anniversary is coming up. I might ask for a kinky new toy....