I mentioned it only as one of the interests of the owner / children that I would have to address for a proposed sale.I could benefit from it (I believe) if I offered some type of lease option.

Lender's typically offer the best terms when they can secure a senior/first position lien.It may be more beneficial to find a partner, instead of a lender, who can help fund your acquisitions.

I did not take up the offer because I have zero knowledge in construction wouldn't know if he made money off our own co-owned property right under my nose.

I've recently been offered 2BR mezzanine, garden and penthouse opportunities there through RETA. 

I see the value if I'm facing a massive tax bill, receive a 50%+ DP, or I could see the value if I'm offering seller financing to a qualified buyer will owner occupy. 

I understand that as one acquires more types of assets, taxes can become more complex, and I want to ensure I'm maximizing my savings.Are there any CPAs in this community who also own real estate and could offer guidance or share their experiences in navigating taxes as a real estate investor?

We actually coached a client to offer a dog photo shoot at his hotel because so few in his area allow dogs.

I was prepared to offer $15,000-$$20,000 to buy it outright. 

I like to figure my estimated cost before I make an offer on the property.

In order to make sure you're optimizing your tax advantages and adhering to all applicable requirements, even while I can offer broad advise, I suggest speaking with a tax professional or accountant who is knowledgeable with real estate taxation.