Hi mymovetospain
Renting your property out can be a nightmare but it can also be beneficial financially.
I would suggest that you approach your local council and see if they are looking for properties like yours to rent out (as you're in London I would assume they will be).
The council will usually take your property on for 3 to 5 years and the rent is guaranteed for this time - you just need to make sure that if there are any maintenance issues they are completed - you can usually get the council to complete these jobs for you with an admin charge, but it's well worth it for peace of mind.
The only issue with renting to the council is the initial outlay of sorting all the health and safety jobs that will need doing, such as fitting a fire door on the kitchen, having a wired up smoke alarm etc. What they do is come to your house and tell you what needs to be done and you just get it done.
You will also find that there are other agencies that rent properties to the council under a similar scheme.
I know they are always looking for properties in West London and I think the scheme is great, especially if you're not planning to move back to the property - and the rent they pay is very good too. I highly recommend it. I'm sure they must be looking for properties in all parts of London.