Hi Kolya,
I have no doubt you will be welcomed warmly at any astro group upon displaying any interest in astonomy in general and other peoples scopes in particular.
Congratulations on your decision to buy a DOB, and on the way you have gone about it to date.
In relation to your choices, I agree completely with everything Raymo has said above.
And if you do a search on dobsonian manuals you should be able to download one in advance to see how easy assembly is. (I know you can with skywatcher manuals at least)
Feel free to ask any questions you have.
Clear skies
Allan