Would buy a small terrace house needing renovation then rent it out, that 100K investment now will be worth a lot more in 30 years time plus all the rental income its generated in 30 years which would pay 2/3rds of my mortgage 
....A good principle but would £100k really be enough to even buy a small terrace house to renovate? You must live up north somewhere to even consider that as financially viable. You might need deeper pockets to be able to continue when it's discovered that the house might need something more structural - Not uncommon and often an unknown until you start taking a building apart.
No I dont live up north currently (Live in Norfolk currently but moving to cornwall in Sept/Oct) but I am from up north originally
I was using myself as an example as im the the process of buying my grandmothers house to renovate (She has recently moved to a Home that caters for Alzheimers, but 7 years ago I promised her that I would buy the house and renovate it myself as she did not want someone outside our family making money on "Her" property
).
So true to my word im buying it and renovating it as a buy to let, it will form part of my retirement fund (in 25 years
).
I think over the long term its hard to beat buying a property and renting it out, yes of course there are risks (But there are risks in ANY investment) but as long as you do your homework and your income can cover the mortgage should it be empty for a while then its well worth it. I am lucky in that I learnt a lot from my parents about buying and renovating property from a young age me and my brother spent time after school and at weekends knocking down walls, filling skips, painting etc etc Happy days!
