Very fine steel wool will be all you need for now... "000" or finer... sometimes they are packaged for cleaning silver wear. Will feel like fleece.
I don't like water near my cases. I don't bother cleaning the inside of the case. If you put any sizing lube on a case, it should come off.
I like the lanoline/iso alcohol combo for lube... RCBS Case Lube 2 works great too.... size then remove with a towel. All I do when making small batches of ammo during load work up.
For costs, easy math is $1 per bang - can vary either side depending on the bullet, powder, primer combo you use but you get the idea.
Competition shooters also add the cost of barrel wear into their costs as they will be updating their barrels on a regular basis.
Any thought on the rifle you prefer? And type of shooting? There are many many good shooting factory rifles but barrel specs from many companies can be quite antiquated which can limit end use performance.
Jerry