You should check the centerstand and find out what the problem was for the previous owner.
There is a trick of inserting washers (or coins) between the coils. This done while on the centerstand, spring extended. When the stand is retracted (spring collapsing), the spring is unloaded and longer. (I may have found the trick on this forum).
That way you can check out the stand without preload and see what isn't right.