you're limiting yourself to spending very little money to start. Your only expenses with any snake are not just going to be the inital cage/tank, snake and prey. You also need substrate, hides, water dish, cleaning supplies, vet expenses and be prepared for additional vet visits and medications, etc. If you can't afford all that to start and can't afford to give your snake the care it needs as soon as it needs it then please reconsider.
Based on your initial criteria I'd say a rubber boa - but they seem hard to get in the U.S. (seem to be more prevalent in Canada). A male Kenyan sand boa would work great - but you must have a heating pad. No snakes need lights - unless you're having trouble getting the heat correct and want to supplement a heating pad with infrared lights.
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My Album
1.0 Ball Python
"Aragorn"
1.0 Kenyan Sand Boa
"Gimli"
0.1 Australian Cattle Dog/Pointer
"Kira"