£140,000 deposit, £20,000 salary, -£5000

Hello all
Im looking into getting a mortgage, I have a property in my name worth £140,000 going on the market this month.
I have -£5000 on a credit card.
I'm on £20,000 pa, payrise next month but not sure that will mean a thing without it being on payslips.

And I would ideally like to get a mortgage of £100,00-£150,000

Is this unrealistic even with my large deposit??
If not, what am I to expect?

Thanks in advance! :)