Fibre split or additonal connection?

[Johnman]

I have a Vumatel fibre connection with Mweb ISP - 200GB/20Mbps and XyXel NBG 418N router. With just me and my wife and moderate usage, this is sufficient. However, we will soon have a (much younger than us) tenant in a freestanding flat on the property - who obviously wants internet. The current signal from the router (even with a booster) is not adequate - due to distance and too many walls.
As I see it I have 4 options:

1. A cable connection from the router to the flat - difficult, but doable.
2. Upgrade the router / booster to improve the signal.
3. Split the current connection to a new router in the flat.
4. Install a second fibre connection to the flat and sign up a new ISP contract.

The first 2 options will result in us having to share the data, but will probably be cheaper options. The ISP may not like option 3 and option 4 will be probably the most expensive - it will be long fibre route from the street to the flat plus a new ISP contract.
Any advice/recommendations?
Am I missing anything?

Johnman

 

[My_King]

My opinion - Option 1

Depends also on the tenant attitude. Will the person be downloading the internet. If not, sure option 1

 

[Johnman]

Thanks - makes sense to determine what the tenant requires. However the flat may in future change into a Airbnb setup, so I should also consider flexibility.

 

[phil77]

I would go with splitting your current internet and splitting costs. You may want a router that "limits" the speed for both of you so that you don't inconvenience each other.