Double taxation - what taxes I will pay - Poland / Brazil

I read topics related to taxes - but we have now 2018 and some rules could changed.

My question is what tax is obliged to be pay by person who
- currently have small business in Poland and pay taxes and social security in Poland
- will move in September to Brazil and will fill form for getting permanent VISA (because of being married with Brazilian)
- will work remotely from Brazil (but for own company registered in Poland for polish customer)
- will be in Brazil from September probably for more than 183 day before going to Poland (probably just for 1-2 month again in 2019 - and there will work of course as person use only laptop for work and internet)
- have flat in Poland that is half rented already and will be rented fully (registered in polish tax institution and pay taxes monthly)

1.  When I will have to start filling tax report in Brazil? I know I will be tax resident after having permanent VISA (if I will ber granted before end of 183 days it will count from the day I'v arrived or get visa? what if after 183 days? It will count from 184 day (it will be 2019) or from day of arrival (september 2018?). Then I need to fill report in 2019 or 2020 april in Brazil?

2. Poland vs Brazil taxes
Now I pay VAT for my invoices 23%. Then I pay income tax 18% - (limit is 85 528 zl which is more or less 85 525 BRL).  Above it is 32% tax. But I can reduce my tax sometimes via my company cost (things important to run company, car etc). I pay 18% and

in Brazil it seems that:
- I will pay 27,5%
- I will pay 15% on house rental (in Poland 8,5%).

Inheritance/Wealth Tax
Brazil has no inheritance or wealth taxes. However, some states may impose a death transfer and a donation/gift tax.

In Poland we have some rules. For example if someone give flat to other close family (I mean to brother/sister/son/daughter) than it is 0%.

My source of knowledge (some thing are possible to be outdated)
- https://internationalliving.com/countries/brazil/taxes/
- https://home.kpmg.com/xx/en/home/insigh … e-tax.html


3. How I should calculate tax estimation in my case and the schedule of taxes? I guess without hiring expert it can be kind of tricky think to do. What other choice I have to cover my small assets? I mean I don't mind paying taxes - but would like not pay double taxes or too much as I'm not currently happy with my wealth and would like to earn more (by work/business/investments) - especially when living in Brazil as it seems more costly country than Poland.

4. Any recommendation for some company/tax advisor?