Preparations for summer camp should begin in January and I know it is very hard to find things and places for you kid when you are strapped for cash. So I have these few suggestions which you may have overlooked but may work for you.
Partner with some other parents form her school if school isn't out yet. Find out what they are doing with their kids and perhaps your kid could be a part of that. Visit some local churches, they may have programs for the summer for children and you may meet some people their you may feel comfortable with for child care options. Check your local Boys & Girls Club if you have one. Personally the YMCA can be expensive but I know they may have scholarships to attend if they are not booked up already.
You may want to find a local trust worthy teen to hire to do actiivities with your child. I live in the city so there is always the local pools, parks, museums, skating rink, etc to keep the kids entertained.
Perhaps your child could volunteer to help at a local day care center (only if your child likes little children).
Bringing her to work isn't going to work for the entire summer. I'm just trying to give you some ideas for thinking outside of the box. It may also be an opportunity for you and her to develop some friendships that are stronger and like family. This is what I had to do while raising the sensational six when they were 10 and under. If I can do this with six children, I am certain you can do this with 1. Stay encouraged.