This is a small amount and some debt recovery agent wont touch anything under £500
Simply not true, dont know where you got that from,
http://www.thomashiggins.com/pages/costs_and_fees.aspx
Cost £2 + VAT to get a letter before action sent and thats normally all you have to do to get paid.
All the do this, then that, then get a solicitor 
drives me mad , costs your time and money and is not necessary, instruct and move on.
I worked for a debt recovery agent for twenty plus years, our minimum amount we recovered was £500, i said "some" so how is it "simply not true 
I'll let you off (this time
) I missed the bit "some".