1) The regulation 1.263(a)-(f) reads that you're able to utilize it for amounts paid during the taxable year.

At one time this was allowed but is no longer legal or acceptable under RESPA regulations. 

I converted my garage to an ADU and now my main house is considered RSO unit since it was built before 1978. I have been airbnb’ing it less than 120 days which was helping me to work/ travel a portion of the year outs...

Diversification across 3 markets also de-risks my investment if local regulations or micro-factors shift negatively in one market.

How do you ensure that properties comply with local regulations and ordinances?

There is federal regulation against it buddy. 

Hey guys What do you think in general for STR in both of this cities I came back from Miami and what ever going on there it’s crazy , I also like Austin area alot but I know more regulation for STR there , in general I think the rental market in Austin it’s not good Median rent is 2-3.3K and house pricing is 400-700K  so it doesn’t worth for long term investment and cashflow , maybe only for appreciation.

The above are made up numbers that will vary based on your market and local regulations but you get the idea. 

Investors can purchase a portion of several properties in the form of shares.Real estate investment funds provide you the chance to invest in real properties with a variety of rules and regulations that are specific to each region.

All bids are to be based on the bidder’s own information and knowledge of the property, learned through his or her own efforts, and not on any representation or comments made by the Committee.The property is being sold free and clear of the lien(s) being foreclosed, and of all interests subsequent in right to that lien.The property is being sold subject to:All taxes due the municipality not foreclosed by this action,Water and sewer use charges not foreclosed by this action,All building and zoning regulations of the municipality which affect this property,All building lines, easements, restrictions and all other matters concerning this property which appear of record,The rights of any person in possession or occupancy of the property who have not been made parties to this foreclosure action,The right of the United States of America to redeem the property, if applicable under Federal law,Any other liens on this property which have not been foreclosed by this action.Further description of the property and further terms of the sale may be obtained from the Committee or from the court file.