Cheapest most reliable best solution? Run a wire to your laptop. In small apartment, I would just do this.
If you are stuck with wifi, the solution is not going to be as easy as adding signal amplifier. Lots of things can impact your wifi, such as:
- How old is your router? There are different router using different wifi protocol with different speed.
- How old is your laptop? Can your wifi run at the same speed as the router?
- Signal amplifier is not going to help if the bottleneck is the router or the laptop.
- If you are living in multi-apartment building, everyone has wifi routers. The signals from your neighbors may interfere with yours - that is why I suggested wired solution.