I've also been interested in UK property after watching shows like "homes under the hammer" and wondering how cosmetic renos seem to be so profitable
When I know back in Brisbane you're bound to lose money if you take on a similar project.
I've found this
website to have a load of info for learning more about the buying process and costs..
I think some of the main differences are: You're more likely to get a bargain at an auction in the UK as they explain
here. There is no stamp duty to pay on a purchase less than £125k, above £125 it's still pretty low comparitively. Holding costs are lower - interest rates are at 3.5%. If you're buying to hold the tenant pays the council tax.
But min deposit for "buy to let" is 25%, (Barclays require 40%) and you need a minimum income - from memory £35k/pa for Lloyds TSB.
I'm not sure what your budget is, so can't recommend any areas in London.. Have a look at
http://www.foxtons.co.uk/ to see where you can afford, and compare them to the rentals to calculate the yields.
I'm not sure what is more common in the UK, self managing or using a PM. Each property I lived in when I was there was self managed, but I think that had more to do with the flat share arrangement I went for.
Good luck, and post any more info you find