hi there, you can use gemma 3 (4B or less depending on your hardware), which requires a much lower spec. However, based on my experiment, the result would be not so good (poor result, very slow response).
I took a couple months on investigating for an optimal solution for chatbot (low specs/cost, quick response, good result), but the conclusion is that there is no solution for low cost high quality. You would have to accept to pay by either cost, response time, or result quality