Fleet Farm has cheap soft-sided tent lights for $10-15, I have one and it’s plenty bright. They’re just soft plastic white bulbs with a LED inside. Or you can buy 5′ rope lights on Amazon that plug into a power bank like you’d charge your cell phone with. I think it was $20/30 with/without the power bank. Both of those have worked really well for me.
that’s what I use. I got one that was normally $40 that is SUPER bright. Found it on sale at cabelas for $20 on day and jumped on it. battery lasts forever and its plenty bright.
This is the one I got.
http://www.cabelas.com/product/BLACK-DIAMOND-ORBIT-LANTERN/1963526.uts?
looks like they’ve come down in price a bit. Works great and you can change its shape so that it doubles as a flashlight