There is no such thing as money friendly
To some people an RM2000 router is still money friendly
And to some people an RM100 router is the only thing they can afford

State your budget

One week is nothing
See for yourself

Is that your own house or are you renting?
If that's your own house, just call a contractor to hack the wall to install a CAT 7 ethernet cable upstairs so that you can install another router

Powerline is neither stable nor reliable

Aiyah, just do lar, some minor hacking only
And the cost won't be that huge since you just want to install 1 ethernet port upstairs, not multiple

Direct cabling between routers will always win when compared to powerline / repeaters / mesh network

State your budget

Buy your own router, that's way better than getting crappy routers from TM with a contract renewal

If you don't use the HyppTV, choose UniFi-Business
This way port number 4 on the AC86U can be used for internet as well

And to answer your next question, yes, UniFi-Business VLAN profile can be used for UniFi home customers too

Meh. TM is not afraid of TIME because of their coverage limitation

You so malas is it to install on your own?

Do some research lah, it's so easy to install and configure your own router

Call TM helpline

I can't advise you regardint the Fibre placement but I would advise you to also add ethernet ports all around the house especially in every room so you can use them in the future

Don't use case but put the cable into the wall (yes you need to hack the wall) instead so you don't see it at all
Yes this might incur more cost but it's worth it
Also, go for CAT7 ethernet cable instead of the older cables for futureproofing

There's even CAT8 now but they are not widely marketed yet

No

Because to TM, ARPU is everything. Especially when they are having huge losses this year

Doesn't matter. It's still crap