@Chris-And-Daniel1 You can, but the problem is that the reviews you will get will be a reflection of the current state of the property, so may be misleading to guests in the future.
But as you upgrade, you could change your listing description to mention that this and that has been changed, and that reviews before XX date reflect the listing before the upgrades were done.
Of course, hosts are usually always making improvements to their properties, but if it's going to end up seeming like a totally different place, it might be better to wait.