ijudge we rent, have a 2.5 yr old and one on the way, and we have been fortunate to find a long-term rent (the owners have emigrated to NZ and use the rent we pay as an income over there).
This, however, did take us 3 goes, as we moved in together when I was pregnant in early 2008, moved again in mid 2009, and then again into our place we have now 6 months ago. I felt terrible for uprooting our little one both times we've moved since he was born, but it really did not seem to bother him as he's so young. I would feel bad about moving him every year and would rather he can stay somewhere for a long period of time, but I think you'd have to have really bad luck to end up moving yearly or something like that.
The problem with renting privately is that you are never going to find a contract with a longer notice period than 2 months, to have real security on paper you would need to have a council / housing association house. Hopefully the private renting sector will change as the government realise it is the only / better option available to an increasing number of families, and start to change the laws to refelct those on the continent more and make private renting more stable for the tenants.
The key I think is to ask pertinent questions when viewing the house about how long realistically the landlord wants to rent the house out for and make it clear that you are looking for somewhere for a few years. Also, a good indicator is if they are happy for you to decorate etc., so you can make it feel like your own. Other posters are right about there being a big difference between those houses which are rented out by landlords as a business or second income, and those who rent their house out whilst they are away temporarily, waiting for the housing market to pick up etc.
We do have an element of instability, yes, but on the plus side we are living in a nice area of the city with great schools, lots of entertainment, culture and green spaces on our doorstep, that we could not afford if we were ever in a position to scrape a deposit together and buy. If someone did drop 40k into our bank account tomorrow so we could buy, we would still end up in a poky house on a rough estate, so I would probably consider investing that money in something else apart from property for my children's future and carrying on renting in an area that makes us all happy.
Taken me a while to get my head around the fact I will probably never own a house, but we are happy in an area we love
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