Generix wrote:I answer your questions out of order:
(1) Voluntary registrations, so long as you have decent evidence of your intention to make taxable supplies, then there should be no issue.
(2) As a small trader/ trader in 2nd hand motor vehicles, you may opt to use the flat rate, cash accounting or more likely the second hand margin scheme. If you opt for the latter record keeping and documentation is VERY VERY important, more so than the former two options, as you effectively pay VAT on the 'profit' rather than the net value (I have simplified the description [before the other tax experts pull me up on it]) of the sale. Keep this in mind. For VAT purposes record keeping is same for Ltd / Sole prop, don't know about accounts etc.
(3) If you register as a sole trader for VAT then all of your business as a sole trader is caught under the VAT rules***, including your other part-time business income (unless you are an employee for the other business - i.e. the business is not yours). I'll leave others to mention about things like registering for self employment and business tax etc.
(4) Practically and administratively there is no difference in deregistering for VAT as a Ltd Co to a sole trader, same for registering.
(5) To be honest with regard to credit, it depends on how much cash you have, turnover, and what you are willing to guarantee, so sometimes these days, directors of Ltd co's end up risking as much (in practical terms) as they would otherwise as a sole trader...all depends who you go to for credit and what your current finances are like.
***Note that I mean any business you run as a sole trader would be caught, even if they are seperate businesses. Also if you register one business as a Ltd Co, and keep the other going as sole trader, then HMRC might consider whether you are attempting to segregate the businesses for VAT avoidance purposes, usually this is only if the businesses are somehow related: obvious example to make the point is a pub seperating the business of selling beer and selling food.
Thanks Generix for your time.
(1) And how long does it normally take for the process? I heard around 4 weeks time, is that correct?
With regards to point (3) I've already described in the other reply the other business is a limited company in an entirely different sector - is a startup so no worries about turnover as yet.
My other concern is if I register a limited company and later decide close the business (when my other business picks up and/or I decide to quit car trading) it will leave a footprint on my credit profile won't it? Does such a record affect the credit worthiness and/or reputation in any way?
And one major concern, I've seen it happening to many even in my family that the accountant did not file the VAT returns correctly as a result of which HMRC dissolved the company. What happens in case of a Sole Trader? They can't dissolve a sole trader can they

so how could they penalise him?