Budgeting for film is always complicated. More so if you have no previous experience. Bottom line, the lower their per episode cost, the more likely they are to profit. Set the cost too low, and you're working for nothing. Try to save money on your main star and the show fails, try to get the best possible star and the show becomes topheavy.
The best advice I can really give you (without spending 20 hours looking over every aspect of your planned production) is to consult with an experienced specialist, and hire them to give you a detailed appraisal.
Budgeting your show is definitely not something you can do for free online.
If you just wanted a ballpark, and you're a newcomer with no following, I'd guestimate that you'd want to come in pretty cheap, like 200k an episode or less. It depends a lot on your target network as well. Sci Fi channel for example pays extremely low for their in house movies, like 110k for a 90 minute film. Netflix, at the height of it's money printer phase, was giving a million dollars to anyone who could spell "sitcom". So there are many factors that would contribute to even a ballpark estimate.