Good advice from @Wishingforwinter
My first property was a shared ownership (not London, and many years ago).
I had no problems at all reselling it, and it was a great way to get onto the property ladder with limited outlay and means. If you are having to pay rent anyway it makes sense to have a stake in the place and benefit from its appreciation, as well as the much greater security of part ownership over rental.
A few things to look out for and think about…
A good location is particularly important for shared ownership when it comes to selling. Also beware of any construction or clauses that might prove difficult to secure a mortgage on in future.
As previously mentioned - costs. These have become more complex (sneaky) over time in some cases, so undertake detailed research.. are there circumstances when, if you miss a payment you could be evicted and forfeit your share? How are costs such as rent calculated and is there any independent appeal? This is particularly pertinent if it’s linked to unknown factors such as inflation, plus a set percentage.
Many shared ownerships are now leasehold (even the houses), which adds a layer of complexity, and greater costs.
As also mentioned, buying a greater share over time will be based on prevailing market value. However, if you’re viewing Shared ownership as a stepping stone to full ownership you’ll have the option to sell when finances improve and your stake will
still be keeping pace with property prices. Putting your investment into a savings account is unlikely to do so (unless prices stagnate or fall).