CCJs for owed rent - upgrading to High Court

Rent Arrears

I have a tenant who has now abandoned her tenancy and moved elsewhere. During the last 3 months of her tenancy she failed to pay rent. As rents became due, I applied for County Court judgements against her. I can reclaim some of the money owed from the deposit but she will still owe over £600 in unpaid rent. I have applied for an been awarded Judgement on the County Court orders (4 of them) which total £670. I have had experience of Bailiffs and was disappointed that they had almost no powers. I am considering elevating the claim to the High Court as a writ issued by the High Court would bring the Sheriffs to her door and they have far more power. I have checked online and found I can do so if the debt is in excess of £600, will cost £60 to pass the case on and this will be payable by the defendant. I am unsure whether the Court will accept 4 CCJ judgements each of less than £200 but totalling in excess of £600, i.e taking the sum of all CCJs as the debt. If not, is it possible to clear the CCJs and raise the issue with the High Court. My final query is: Is it possible to get an order from the Court that she has a percentage of her wage deducted until her debt is cleared. I am able to supply the name and address of her employer.