Married to Russian Citizen abroad.

I am a 26 year old British citizen with my 27 year old Russian girlfriend living in the Czech Republic(Prague).

We are both working here for the past 3 years, my girlfriend has been here for just under 5 years total(including 2 years of university study in English).

We plan in the next two years to get married officially and to move to the UK, we currently own a flat together in Prague and pay a mortgage together. Her English level is fluent.

We want to plan ahead the best way to do this, we cannot stand to be apart and do not want it. We see on the Gov website, that I need to be earning £18,600 per year(I am assuming this is before tax). One question is, can I use my income here in Prague as this proof?(I currently earn 584,000czk per year before tax, google exchanges this to £18,916). If it helps, my girlfriend is earning slightly more per year in Prague(equivalent £22,600 before tax).

Is it possible? Would I have to disregard this income and go to the UK, get a job higher than £18,600 before tax and work for 6 months and only then she could apply??

Is it possible I would go, get the job and work and she would basically be with me on a visitor visa in the UK and apply from within the UK for a spouse visa?

Additional question: If we were to sell our flat, just before moving, we could theoretically have £25,000 in savings.

You can use your foreign income to meet the financial requirement but you must have the job offer from UK employer going to start within 3 months on arrival. Also note that the applicant's foreign income won't be considered but cash savings can be. Moreover, sale proceeds from the sale of property can also be used to meet the requirement without needing these to be held from the last 6 months but unfortunately £25000 alone would be insufficient. She will also have to sit for A1 ielts life skills test regardless of how much fluent she is in English.

It won't be possible to apply for a Spouse visa while in the UK as a visitor.