Hi there,
Renting out a property is just like any other business; you are liable for tax on any profit you make. The mortgage does not come into the equation as this is what you pay to buy the property. Its value will be yours, assuming you keep up the payments on it and in due course it will have a higher value than that which you paid or are paying for it. Trust me, property values will rise again, they always do, it just takes time.
What you need to do is run this as a business, keep a simple account book, which shows the date of monies in from rent and monies out in expenditure for maintenance, advertising, alterations etc.
If you deduct monies out from monies in, the difference is profit and this is what you will pay tax on. If you are currently unemployed you may be able to claim your tax free allowance against the profit, meaning you may not actually have a profit to pay tax on. Only the figures will show this, but be aware, if you are claiming any benefits, these add to your income for tax purposes.
Please make sure the accountant you choose is one you can trust, better to have one recommended to you than take pot luck in the yellow pages. They should point out without you having to enquire, all the items you can claim against tax. If they don’t, beware, at the end of the day, the more work the accountant does the more it costs you. Having said that, your accountancy fees are off-settable against your profit!
Best of luck