If you are a sole trader you can still “trade as” a company name, so you can call yourself “ABC Futons for Kittens” and this can be shown on your business cheques and Bank payments, statements etc. The main advantage of being a sole-trader is that the tax and other similar issues are simpler and less likely to require professional accounting advice etc.
You can start up very quickly and be trading almost instantaneously. If you are looking for a bank, then take the best (cheapest) deal that you can get from any of the major high street brands. If you can get two years of free banking that would be good. Currently the Alliance & Leicester (soon to be renamed Santander) offer free business banking which has saved me thousands of pounds in the last four years. If you are banking lots of cash, then the may not be a feasible option.
The point of having a Limited company is that you are limiting the Liability of yourself, personally. The company itself can have debt (normally from other traders foolish enough to have given it) and if your company goes down, then you, personally, need not necessarily have to pay it back. It would be essential, if you are seriously looking to run a Ltd company, that you get professional advice on this.
I know of several companies who have gone bust, where the business owners have got away pretty much scott-free, often owing me a few grand...........no , I'm not bitter......well maybe just a tad!
I would on the whole advocate that (if you can afford it) you spend around £50 on getting a logo designed. For this price, you should be given around three options for a logo. For this cost, it should be fairly professional looking.
I think you could spend an awful lot more money without necessarily getting anything much better. I would recommended very highly using www.fatflyers.co.uk in Cheltenham who have made some really good logos for me in the past couple of years.
Business cards are very cheap to get printed nowadays. If you really intend to dish them out (which you should) then you could perhaps get several thousand printed at a time, perhaps 5000. Of course, in getting lots done, you need to be fairly sure that you won't be needing to alter the details too quickly.
If you are looking for a very short run of printing, then there are some bargains to be found on the internet, just google the search term “cheap business cards”. For large print runs, especially if you want full colour and print on both sides, I would again say that Fat Flyers ltd. did me a good price and good service.