Hey Shreyas, welcome to this community!
What you are implying means that Freetrade should offer completely free service, which is not a sustainable business model since they pay salaries to staff and need at least some return on investment
All of the Freetrade’s fees are listed here. You will not be expected to pay anything else other than what has been transparently shared prior to the launch. The pricing schedule is also available in the app and on the website.
You are correct, fractional shares are not yet available but Freetrade has set their target to offer these in 2019 alongside several other major additions to the services they provide.
This represents a 1.25% difference. 0.45% is the FX payable and the remainder is most likely the intraday fluctuation (which can change in a matter of seconds) and it is out of Freetrade’s control. Also, Tesla is quite a volatile stock and tends to jump quite significantly.