Tl;DR: You would be nuts to request compensation if you weren't asked to complete the work. Businesses do NOT pay for services just because someone "feels" like doing them. And you run the risk of losing your "friend" and gaining a bad word-of-mouth reputation.
Think of it this way.... you get a flat tire and take it to the local tire shop to get it repaired. While the are fixing the tire, they decide on their own to rebuild the engine too. Would you expect to see an invoice for a few hundred or thousand dollars to cover the engine rebuild? Would you be happy seeing that invoice?
I'm merely basing this on what you posted. I wasn't part of the conversations and clearly there may be details you've left out.
This is unclear.
"I stepped in"...
Did she ask you to fix the form and then you did more because you felt you wanted to build it better?
Were you ever asked by the company to continue work or was it just something you felt like doing?
Based upon what you posted here you would be a bit crazy to think you should be compensated. If no one ever asked you to, as you put it, "rebuild" things then it was your choice to do so and you can't hold anyone financially responsible because you chose to do more than was asked.
Financial obligations have to be at least discussed before you have any footing. At the very least a specific request to do the work is required. In the end, without a written agreement or even a discussion you are simply out of steam.
That being posted, sure you can ask for compensation. It'll take some internal fortitude. You just need to be prepared for possible outcomes:
- They agree and pay you want you ask (yeah.. good luck with this.
It's a long shot.)
- They agree but want to negotiate as to how much they will pay. However, be prepared for low-ball pricing since they never requested the work. Would you be okay with a couple hundred dollars? Or even $50.00? Are you going to try and talk them higher. What if that leads to items 3, 4, or 5 below?
- They disagree with any obligation, but understand why you feel it may be deserved. However, without their request to complete the work they won't pay you anything. They are happy to use the site and relay your name to anyone who asks, but they aren't going to pay. So, they are fine with things, will you be? Will there be some resentment on your part if they refuse to pay anything? Are you going to lose your "friend" over this?
- They disagree with any obligation and don't want the site. They won't pay you anything, find it funny you even ask, and have no intention of using the site. They may even dislike the site. They are offended you took it upon yourself to rework something they didn't request. And while they don't feel you are trying to take advantage of them, they do feel insulted. This may lead to less-than-favorable word of mouth and it may cause some stress with your "friend". Will you be okay with that? Doing all the work and they won't use it or pay for it? If you would be okay with that... why even bother asking for compensation?
- They disagree with any obligation and they are flat-out insulted and feel like you are trying to steal from them or otherwise rip them off. This creates a business who, when asked, may not have great things to say about your work. Are you okay with that? Will you lose your "friend" over this?
Be aware, in my experience the most likely outcomes are 3, 4, and 5 above.
Number 2 above is possible but it's very rare to find any business willing to pay for something they didn't request. That's not how business survive.
If they agree to #1 above, hold onto them as a client as best you can, because I've never heard of that happening. It's like finding a unicorn or catching a rainbow.