What type of investment strategy are you interested in?

Both FNMA and FHLMC permit this, under the following circumstances: Notes: For all such transfers affecting mortgage loans purchased or securitized by Fannie Mae on or after June 1, 2016, the transferee is not required to occupy the propertya limited liability company (LLC), provided thatthe mortgage loan was purchased or securitized by Fannie Mae on or after June 1, 2016, andthe LLC is controlled by the original borrower or the original borrower owns a majority interest in the LLC, and if the transfer results in a permitted change of occupancy type to an investment property, such change does not violate the security instrument (for example, the 12 month occupancy requirement for a principal residence).The servicer must notify the borrower that a property transferred to an LLC must be transferred back to a natural person prior to any subsequent refinance application in order to meet Fannie Mae’s Selling Guide underwriting requirements.Citation: D1-4.1-02: Allowable Exemptions Due to the Type of Transfer (04/13/2022)Now, you will still have the Note and reporting in your name individually and will still be personally responsible for the mortgage and most likely, the manner of transfer will enable any litigant to pierce the veil of your LLC, but you'll have what you wanted, for whatever reason. 

It usually comes down to the type of renter you get.

Initially, I was hesitant due to the lack of information available about Invest1 properties, as their website is a very nondescript page without any solid information about who they are or the type of properties they offer.

4- Finally what price range / square meter / type of property (house VS Apartment) would you look for. you as an investor that will appeal to the Market. 

They avoid the depreciation seen with a tiny home as you describe or that of a HUD-type product and are generally quite well made.

This will depend on the type of loan, size of the deal, experience, FICO, and property location.

Second, do you know what lists you want and what type of properties?

Quote from @Adrian Moening: You've already spent more time typing this narrative than you should have spent on the entire ordeal.This is a very common landlord experience.

That is the law that regulates the type of activity you are describing.Telephone Consumer Protection Act 47 U.S.C. § 227SEC. 227. [47 U.S.C. 227] RESTRICTIONS ON THE USE OF TELEPHONE EQUIPMENThttps://www.fcc.gov/sites/default/files/tcpa-rules.pdf