Bigmac and OP.

Perhaps I have come up with another way for you to hit the salary requirement target??
When I lived in the UK, I was self employed in the building game.. Now if I worked for a contractor,I had to give them them my self employed tax card (Cant remember the exact name for it) so every penny earned had to be declared..
All of my work for my final 10 years however was working directly for clients,customers homeowners etc etc and had no longer any use for the tax card..
This meant that I did my own accounts (with help of CPA) and declared whatever I wished..
Anybody can become self employed,even if they have a full or part time job.. Perhaps your S/E work is done at weekends etc..

Do you get my point?? How hard will it be to declare the salary you need (for visa requirements) yourself??
Sure there will be a bit more tax to pay but this is one surefire method of hitting the 18,600 sum..
If it were me I`d declare around the 25k mark.. I actually did this once before we applied for a mortgage (income requirement)..Worked like a dream.
Others may disagree but that is what I would do....I would do it in a heartbeat.

http://www.hmrc.gov.uk/selfemployed/