^ Disagree with some replies. NO, It won't happen as soon as you registered your business. But your bank account transactions do it for you even without a BR.
The reputation of the audit firm doesn't matter, just keep your documents for all the transactions in relevant order. But someone(audit firm / charted accountant) need to audit your accounts because they (the GOV/ interested parties) won't believe your accounts / financial statements unless someone certifies it ( true & fair view). To do that, you don't need to go to top reputed audit firms in Sri Lanka, haha. Find a small/ medium audit firm & they do the job for you. Which is cost effective & don't go to the reputed top audit firms unless you can effort. Keep your side clean & then nothing matters. If you have tax knowledge, fill the tax returns your own.
Stop worry about taxes son. Just do your business & account/record all your transactions.