Is it permissible for me to help a friend take out an interest-bearing loan, translate his documents, and guide him in investing, and is it permissible for me to take a fee for that, and will I bear sin if he commits acts of disobedience in his home or in the hotel he will rent out?

Borrowing with interest (riba) is forbidden. Whoever has engaged in it must repent to Allah. It is permissible for him to invest the borrowed money or to purchase permissible things with it. It is permissible to guide the borrower to permissible investments and to take a fee for the services rendered. It is permissible to buy a house and rent it out for residential purposes, and there is no sin upon the landlord if the tenant commits a sin therein, as long as the rental was not initially for the purpose of committing that sin. It is permissible to buy a hotel and rent it out, provided that no forbidden things are offered there. In summary: Assisting and guiding towards permissible investments and taking a fee for them is permissible. However, aiding or guiding towards forbidden investments is not permissible.