Hi and welcome
I,ll start with your last question.You will need to check the terms and conditions of your employment as quite often there is a clause that affects your employment if you enter into an insolvency agreement.
Once in an IVA you can end it early if you have a lump sum[from a friend,family or equity from a property]In these cases you can often just pay in an amount that returns the original dividend proposed.If you have a windfall[inheritance/lottery win]then again you can end your IVA early but you will need to pay all of the windfall over upto the value of your original full debt plus IP fees and statutory interest.
You will be required to pay in more to your IVA if your disposible income increases and this will return a higher dividend to your creditors and will not conclude your IVA early unless you have paid the full 100p dividend plus IP costs and possibly interest.
Regards
Andy Davie
IVA.co.uk Spokesperson
About me:
http://www.iva.co.uk/andy_davie_profile.asp
IVA Helpline: 0800 197 4838
http://www.iva.co.uk/iva_helpline.asp