AjanleKoko:

I think your choices are good. For audit I presume you mean CISA. Not a bad certification to have under your belt. I also like the British Computer Society thingie. I have never heard of it though.
Start from the IIBA's CBAP certification. IIBA is the International Institute of Business Analysis. Canadian-based, I think.
Check out their website on http://www.theiiba.org. Although they have a rigid 7,500 hours or 5 years business analysis experience, I imagine they would have some sort of track you can use to start the upskilling process.
I'm also considering writing the CBAP examination this year. So you are in good company.

I would also recommend that you start looking at BPM as well. You can learn about some of the BPM methodologies like Six Sigma and LEAN Six Sigma. Those ones are basically courses that you attend to get certified. Although I don't know of any organization using Six Sigma in Nigeria, but it's still a good one for international look and feel on your CVs.
Hope this helped somewhat.

Boss, good morning and I'm very sorry for disturbing you. I will like to discuss with you about IIBA. Pleaseeee