Somebody with income from land & property has to fill in a self-assessment tax return that must be filed one year after the end of the tax year to which the income relates.
If you do not file a self -assessment tax return in time, there are penalites. £100 for the first 6 months, which doubles in 6 months and is tax geared after a year.
Of course, interest and late surcharges apply automatically for unpaid tax.
I would advice you to come out, especially since the tax involved is not significant.
As to the accountancy costs, no accountant would give an estimate without looking at what exactly is involved. Nevertheless, as they say, the true accounting cost is not only the accounting fees but the tax savings and the earnings from the service provided.
Hope this helps.
Demetris Savva BA FCCA
http://www.tax-accounting-london.info