> One way out could be to tax the value gain at the time of sale
Stamp duty in the UK, horrendous tax. It's better than nothing at offsetting the unearned increase in house (land) value, but far worse than a regular tax.
If you live somewhere for 10 years, then move, then repeat for 40 years, you pay far more than if you never move. This encourages people to live in less suitable houses for longer.
As to your worry about land values increasing -- the owner is deriving benefit. The higher the land value is, the more benefit the owner gets from the land.
Stamp duty in the UK, horrendous tax. It's better than nothing at offsetting the unearned increase in house (land) value, but far worse than a regular tax.
If you live somewhere for 10 years, then move, then repeat for 40 years, you pay far more than if you never move. This encourages people to live in less suitable houses for longer.
As to your worry about land values increasing -- the owner is deriving benefit. The higher the land value is, the more benefit the owner gets from the land.