Don't think they will check your turnover unless its something outrages, however by the looks of most of them offering it, you need the account you use for business to be with them, so if say only 10k went through it for the year and you're telling them you turnover 20k that might look at a bit suspect. The banks are lending out the money but the government is guaranteeing it, so the banks won't be as cautious lending it to you as they would with there own money.
