I should add another tip on the door locks.

Another tip I saw on a post was to keep giving the lead/ applicant more "chores" eventually they give up and then it's on them for not getting you that info.   

Do you have any tips or news I can use to get an idea of the market there ?

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@Dmitriy Fomichenko Thanks for the tips!

@Dmitriy Fomichenko thanks for the tips I am already using some of them!

Some of it ranges from tip-toeing on the lines of legality to downright illegal. 

Bonus tip, record the incoming calls so you can get a good chuckle out of all the threats to call the FBI for mail fraud.

Does anybody have a tip how to connect with potential owners?

Any tips on what range of approaches I may find?