Hi Lee, i'm a qualified spark and having been for a number of years, in my honest opinion if you wanted to be in the position to offer full peridioic inspection reports you need to be a fully competent electrician with alot of experience. Intensive courses are availble for people with experience already (like kitchen fitters and plumbers) who need the qualification for part p to carry on with their day to day jobs (moving sockets in kitchens, replace electric showers, install heating controls etc). If you are inspecting entire installations you need to know the regs back to front and even if that could be tought in a short course you wouldnt gain the experience and instinct to find the hidden nasties that time served electricians get the gut instinct to find. I dont want to put you off retraining, but only recomend you consider a proper apprentiship if you do. Also bear in mind that pretty much every periodic report will fail somewhere as anything installed pre 2008 is unlikely to meet current regs, in which case after doing the report you next question from the client is "can you fix it and make it comply". As an electrician I dont find pat testing particularly profitable but it is a way of getting my foot in the door for extra business, not sure it works the other way round.