You still want to complete the Level 2 Level 3 NVQ 2330 (now 2357) don't do quick courses like PART P. Other courses such as the 2394/2395 Initial verification and periodic inspection and testing as well as 2382 the 17TH Edition are all extra courses you do on top of your 2357 so don't go doing these first thinking you'll be a fully qualified electrician, but that said they're worth doing as you will need them.
 
 
Best bet in your situation is to do a home study course for the 2357 with a reputable college, this is a hard way to learn but it does allow you to keep doing previous jobs if you need that to fund the course. Or ideally work part time say 3 days a week, attend college 1 day a week and work for cheap or free for electrical experience on the other day. You will need experience so weekend and evening electrical work with a qualified electrician will be needed, your LEVEL 3 often you'll need to be in FULL TIME employment else you'll struggle and your NVQ portfolio will be non existent. Often the college kitty which is what is allowed to be spent on apprentices under the age of 19 is allowed to be used on adult learners if this has not already been used up by the young apprentices, so that would be definitely worth finding out about. But if you have to pay for it yourself you'll be looking at between ÂŁ4-6k for the 2357 I'd say. Look for a decent college, ask around or ask an electrician in your area.