Why own a property if you don't use it/enter it?
The property system was created with an automated system to sell inactive properties which didn't work as it should.
Only recently has an override command for HQ members to manually sell properties and they do so under their own discretion.
Highly sought after properties that are inactive will be sold without a second guess, al other inactive properties will also be sold as the HQ member feels necessary.
If you purchase a property and do not enter it, we won't be able to see if the property is active or inactive as it won't have any entry date logged therefore you may lose your property.
It's not that difficult to enter the property once a week or so when you're in-game more than once a week.
Well... so that you are using it? Even if it will after all in many cases, simply be you entering the property every now and then...
I have to admit that this system is more proper than in rs4... Where you simply had to be active in game.
You actually had to enter the properties in RS4 too.