If you are shooting for a student film or a basic film that you'll use to hone your directorial skills. you can shoot on just about anything. Heck use a flip phone camera, use a 7D, use a ALEXA, use anything.. Realistically, shooting a mini series is laudable, but not very smart. Shoot a few 5 min short subject projects that will teach you what you know and what you don't know. shoot, edit and COMPLETE each of the small short subject projects... Shoot on whatever you have for now. Don't sweat the camera, work on your skills of directing cast, dealing with crew, working in budget (or lack of budget), learn what can and can't be done. Play with lighting, play with blocking and shot selections, experiment...
Sound in film is critical. My opinion is that it is 51% of the project. You can destroy a great image with bad audio, and you can fix a borderline image with good audio. You can sell shots that otherwise won't work with audio. If you can't understand the dialogue and you have to strain to hear it, your audience is going to shut down, and you lose "suspended disbelief", and lose the audience. It's not only location audio that you need to be careful with, it's post sound design and music. These things will make or break your film. Lots of newbie film makers will spend hours getting the perfect shot only to completely blow it by not spending time on audio. No matter how much its banged into them, they just never get it until they mature in their film making. Get a good shotgun mic and a boom. Get a recording system. There are inexpensive systems that match the rest of the quality of what you are doing. Check your locations in advance with the sound recordist before the shoot day. MAk sure you visit at the time of day you will be shooting. It might be nice and quiet on Sunday morning, but insane Tuesday at rush hour. Take the time to deal with sound issues with the same energy you would with lighting, camera or cast direction. You'll be happier, save money, and have a better product in the end.
Edit each piece 3 different ways, re shoot one and see how better the second one is from the first try. Get you chops together first... THEN... when you have a basic understanding of what it takes and what you level of ability is, shoot your mini series.
Again, if you are going to go ahead and shoot a mini series, have realistic goals. you'll not only need a camera, but lenses, lights, props, locations, crew, cast, food, permits, insurance, post services, and more. So make sure you balance your budget to cover more than your camera. If you want a good cheap camera, you won't find it. You can get a camera that works for your budget. Heck, a used Cannon 7D body can be had for your budget. But you'll need to rent or purchase a couple lenses. I'd recommend a 35mm, 50mm, 24mm, and maybe one more. You want Prime lenses, but you probably don't have a budget to purchase primes... so look on line to rent.
You'll get much more production value for your dollar if you find a good crew, cast, good lighting, good locations... You'll also get happier crew and cast if you feed, and treat them well, since you are probably not paying them.
best of luck in your new adventure!
Cheers
geo