I started lessons at a chain where the prices were high, but they offered practice sessions and group classes with teachers to dance with. Taking private lessons with an independent instructor is cheaper per hour but then where do you practice? I went to an independent studio and took some classes that were very reasonable but there was no one to dance with. Any advice?

Ask if the studio offers weekly parties.
These are usually held on a Friday night and open to students of all levels to come, mix, dance and have a great time.
If not, google search to see if there are locations near you that offer dancing in a social atmosphere. Be sure to research the establishment(s) thus providing a safe area to cut the rug, as it were.

Have fun :)

Aren't you in Phoenix??

I had this problem too. Places I have practiced when I have someone to practice with:

at the park, paved area, brought out a boom box with a waltz CD and we practiced.

At home, removed some furniture and made a small space. Not ideal but OK.

The instructor does monthly dance parties which are inexpensive.

And when we take a private lesson or several, we can take the class that covers that dance for a lower price and thus the class is for review and practice and the private lesson time is for really working on the new things and on perfecting the steps we know.

Good luck.

My answer to "Where to practice?'' is: anywhere. My fiance and I have danced at clubs, bars, outdoor festivals, back yards, living rooms, parades, restaurant lobbies, on sidewalks, parking lots, fields...if there's a bare patch of floor or ground, we'll dance on it. (Appropriate footwear advised).
It's impossible not to dance, in my opinion, if there's good music playing. (Especially live).
I have even been known to practice by myself while pushing the grocery cart.
If you don't have a regular partner, see if there are people at your studio who'd like to get together outside of class and practice.
It should not be necessary to spend lots of money (if any) to practice.
I've noticed some people at my studio don't do any dancing outside the studio. I think this is a gigantic mistake. Mainly, because they're missing out on a lot of fun. And they're emptying their wallet in order to practice.
Do you live in or near a large city? Where I live, there are a number of clubs and bars with music, live and recorded, where people go to dance. It isn't necessary to go with a partner - people dance with each other. You might have to ask around to find out where places are in your area, and what are the nice places and what aren't, but I hope there are some good places you could go. In my area, there are especially several places to dance Lindy, EC swing, WC swing, salsa, tango and ballroom. Most of these have no cover or a nominal cover of $5 or $10 for the evening. I'm made I don't know how many friends going to these places.
Good luck to you.