Apparently the companies in Greece have very bad lines and when you pay for 25Mb/s they give you less than half of that. In the contract it actually even states that as long as it’s above 9 Mb/s it’s not a violation of contract. I was wondering if buying a better router instead of the one provided to me would make a difference
Sounds like a crappy wisp, why not use Starlink?
Your connection is probably some species of xDSL (do you plug your modem/router into a phone port?) which falls off very badly based on distance from the distribution point, so it is unlikely to be the fault of your hardware unless it is twenty years old.
I suggest looking into Starlink or 4G/5G fixed wireless, which have their own downsides (latency, basically) but will absolutely do better than 25Mbs.
Doesn’t sound like a router would help you! In terms of DSL there are many failure points within the equation.
Starts with, the backbone is generally not supporting higher speeds in your area or they have limited high speed ports available only. Second the distance from main hub to the distribution hub in your street is long, which means the speed available at the distribution box at your house is already limited. Then it is based on the quality of the cables and e.g. TAE box. If they are bad this will limited the speed as well.
Example 250 Mbit is generally available, but there are no free 250 ports, so they give you 100. Because the distance to your street is long, there is already damping down to 80. In worst case the connection from the street distribution box to your house distribution box is rubbish, it is damping down to 70. Now due to shitty cables from the house distribution box your apartment you loose another 20 Mbit and ending up with 50 Mbit.
Here in Germany you can at least meter it with an app, go back to the ISP and telling them that you resign because they cannot deliver what is contractually agreed. Usually they simply adjust the price.
A better modem only helps if it cannot utilise the 50 only pulling 45. Not a wifi problem.