I'm on a budget, but I actually budget my chameleon into it. This might be a useful breakdown of what I did. Note, this is all that I can roughly remember. And the day I brought chief home I had NO, and I mean, NOOOOO set up or anything at all for him. I literally bought all of his essentials from the repticon show I found him at.
Chameleon: $150 (he was a deal as a year old cham but I think he was a owner surrender)
Cage: 18x18x36 reptibreeze $70 (repticon show) (upgrading to a DIY 24x24x48 soon: $95)
Assorted types of vines: $40 (repticon and pet stores)
Mistking: $120
Little dripper: $10 (local pet store)
UVB bulb: $20 (reptisun 5.0)(repticon show)
Basking light housing with dimmer feature: $20 (repticon)
Basking bulb: $10 (you can use household bulbs, I tried 4 different ones and couldn't get the temp to where I needed it to be. I have an actual reptile basking bulb that can get very hot (enough for a beardie) but I have a dimmer switch on the fixture and can raise or lower it and it stays around 87-88 degrees... Hence why temperature measuring devices are absolutely needed!)
UVB fixture: zoomed $25 (amazon)
Hand sprayer: $1-3 (anywhere - try the 'dolla' store)

Calcium supplements: $16 (for calcium w/o D3, with D3 and multivitamin) (repticon)
Crickets: 25-50 every week and a half from the hardware store: $3
Stuff to gut load feeders with: $3-12 bucks depending on what (fruits, veggies, cricket crack, etc etc) and how often you buy
Hornworms: $8 cup shipped (I buy online) (25-30 worms) (lasts chief about 3 weeks - if they get too big I give them to a buddy who has a beardie)
Silkworms: $8 cup shipped (I buy online) (25-30 worms) (lasts about the same as horn worms, they grow quickly like horns)
Dubia breeder start up kit from GA CRICKETS: $25, but you can get them anywhere for various prices if you don't want to breed them.
Heat mats for dubias (so they'll breed): $10 (petsmart)
Temperature gun: $39 (lowes)
Analog temp/humidity gauges: about $8 each (repticon)(I have two)
Humidifier: $who knows, I've always had it. But if your air gets dry and misting doesn't help, these gizmos are awesome to have.
Live plants: I picked up two Pothos plants for $5 each (lowes)
Drainage set up (we literally threw it together in a urgent hurry so it's not the greatest but it's meant as a 'for now/termporary' thing, and it works fine for me.
Ulility sink: $49 (lowes)
2x4's cut so the cage sits in the sink: $3 (lowes)
Buckets for dirty drainage water, and one for mistking water: $5 (lowes) any bucket can be used...
Vet checkup: this varies with different vets
Examination: $75
Fecal: $17
X-rays: $75 each
This is really just to give you an idea of a chameleons costs... It varies with everyone.... Best thing to do on a budget is buy one thing at a time, that way your not killing yourself financially. Then you'll take the time to order what you want for the best price possible. But also factor in emergency veterinary costs too. These little guys can have some serious bills add up when there's something wrong with them.
I'm in college, work full time at just a smidge above minimum wage while still paying for college costs, car, fuel, insurance, groceries, etc. but I budget big time and it helps me. But also think of your living situation, do you have someone to check in on your chameleon IF you go out of town for more than a day? Is there someone in your household that could help you out time to time? Every once in a while I'll ask my boyfriend if he'll drop some ready dusted crickets in for me if I have to leave for work earlier than chiefs lights come on in the mornings. Plus some time to do a deep clean on the cage (I take his outside and soap it up and hose it down) plus your weekly tidy ups.
I spend countless hours a week on this forum, before I got Chief, and now. That is priceless

I really hope this helps! I'm still quite the newbie.