A Polish MP is working as a handyman in London as he tries to find out why so many young Poles come to the UK.
Artur Debski believes learning from UK strengths can help Poland tackle its "dangerous" emigration problem.
He arrived on 5 April to live as a migrant - and said he quickly found it was "not possible" to survive in London on his self-imposed £100 weekly budget.
But he said Britain's "friendly" system attracted businesses and people - while the London Underground was "very good".
Mr Debski told the BBC that London was a "special city" and all the British people he had met were "very nice".
One of the first things he did in the UK was visit a job centre, but he said he did not find it useful and instead asked a Polish person for a list of employers to call.
This led to a job with a building firm, renovating an office in Harrow.
He described his role as: "Handyman with a hammer".
Mr Debski, of Polish opposition party Your Movement, said he had begun to see why Polish people came to Britain.
Hundreds of thousands of Poles have moved to the UK since Poland joined the European Union in 2004.
Polish government figures suggest 65,650 Polish people emigrated to the UK in 2008 alone, with 49,000 arriving in 2012.
And the 2011 census found there were 579,000 Polish-born people living in the UK - a 10-fold increase from a decade earlier.
"The British system is friendly for business and for people," Mr Debski said.
"The Polish system is very restricted."
He said this restrictiveness could be seen in many aspects of life in Poland, from the powerful influence of the Catholic Church to "crazy" penalties for offences such as smoking marijuana, which he said could be punished by six months in prison.
According to Poland's Statistical Office, there were 2.13 million Poles living abroad at the end of 2012.
Mr Debski said the Polish government must act to keep its people from leaving - because in another 10 years it would be "too late".
"It is very dangerous for Poland," he said.
"Poland has improved since it joined the EU, but it is improving slowly."
He said a survey of young Poles showed just 17% would never consider moving abroad - and 2013 was the first year in the last 60 when more people had died in Poland than were born.
One vital improvement Poland must make is to help businesses more, he said, adding that his country could learn from British government policies such as a £2,000 tax cut for small businesses.
Mr Debski, 45, said he had also discovered some of the difficulties faced by people arriving in the UK from Poland.
He met a group of workers from Luton who claimed they were being discriminated against, and his personal experience showed him the financial difficulties faced by new arrivals.
"A room in a house is very expensive, the Underground and buses are very expensive," he said.
He said he abandoned his £100 weekly budget after three days.
"It's not possible," he said.
"Food isn't very expensive but £100 a week is not enough."
He said he was being paid £267 per week after tax for six days' work - eight hours on weekdays and six hours on Saturday.
One major problem he encountered was finding somewhere cheap to stay.
He spent his first night on a mattress on a friend's floor, and then a Polish woman offered him a "small room" for £28 a night.
After that he paid for a room in a house near his work for two nights, and he is now staying in Poplar, east London, in a house belonging to a Polish man who is visiting Poland.
Mr Debski, who expects to return to Poland around 22 April, said he was grateful for the temporary home - and did not mind the "43-minute journey to work" on London's "great" transport system.
A spokesman for the Polish embassy in London said: "The impact of migration for Poland's socio-economic situation has been certainly significant, yet its record remains relatively difficult to estimate.
"In the short-term perspective, the opening of European markets may have eased the tensions within the Polish labour market."
The reduction in the workforce was counteracted by the amount of money sent back to Polish workers' families, which played a role in reducing poverty, he added.
"In a longer term, people who will return to Poland will not only bring their savings to open new businesses, but also their acquired professional, social, and political experience, thus contributing to the development of the country," said the spokesman.