Hybrid roles at start-ups?

I've been networking with some tech start-ups to potentially plan an exit into them in about a year. Nothing is written in stone but if they manage to reach the next stage of funding they would be looking to hire me as a finance and strategy professional.

All that sounds good however because these teams run lean I would likely get a hybrid role where on top of my finance and strategy responsibilities I'd also have analytics responsibilities. Nothing close to being a full time engineer but I should be able to build working prototypes of my own ideas that would then at a later stage be passed on to the engineers to be refined. I am not too worried about this but it does mean that I can't go soft on my non-finance skills and I was curious if anyone has experience in similar roles?

In general I'd love to hear anyone's experiences as a finance professional in an early stage start-up. If it is normal to tie other responsibilities into the role like what would happen in my case and how you handled it/felt about it. Also I would make sure to only join a start-up after they just recently get funded so that they can afford me for at least one year but I am curious about how easy it is to get back into the corporate world if your start-up venture fails?