In answer Ben
1) how long have you known each other? - Five weeks
2) how old is she? - 44 years
3) who is the 'driver' of your communication? - Both really
4) have you only texted or also spoken via camera? - Texted and a short phone call, she says her mobile not running for international calls and she used a common meeting booth, sent her number but can't get through, perhaps that's me though.
5) have you seen any official documents? - Yes, she very recently got a new passport as she said she was going to, looks legit.
6) have you connected via social media - No
(Show me who your friends are, and I'll tell you who you are).
7) has she offered you to visit her too? - No
has she shown you 'around' - photos of her surroundings, where she lives, her place of work… - Yes, house pics and wok pics sometimes with her company badge on.
The golden rule of thumb is that meeting in real life requires trust, based on patience and good will.
The more people let you in, the more serious they are.

She asks for £450 for return flights, not so much, I am not rich man by any means but her texts seem to 'scan well', she sent many photos, none of a 'candid' nature but slightly posed, I gather that's common even on here that the ladies do this.

A friend suggested that I 'google image' her pics to see if they show up anywhere else and none do.

She was 'woman mad' with me when I asked if she was 'really real' and that I guessed that 90% + of Russian women asking for money are scammers