Where as a hot home just listed would most likely sell out right or the seller could get more down and a higher rate.  

I am wanting to know if I could make the sides out of wood and cover them with hardie backed board (concrete board typically used to attach tile on) to protect wood frame from getting to hot and catching fire.

Just a little too hot for me right now.

Also, it's located in a hot pocket in San Juan, PR capital.

I can tell you the area and the price point are HOT!

If its a hot market you might have to make an offer before getting in to see it, which may sound scary, but if you have a good team its not a big deal.

Having just bought my personal residence, I am aware that the market is pretty hot in some areas.

Other house is in mid-town, newly 'hot' area, so I see more opportunity for growth there...but I may be wrong...recession saw many houses here drop 50% or more, especially on the high end...Lastly, if you want to build be sure to check the SDC's for water, sewer, parks, traffic etc.

The outgoing pipe from the boiler gets hot for about 20 feet, then it is cold by the time the pipe makes a 90 degree vertical turn and rises from the basement to the second floor.

Unless you have a model which can 100% predict where the next hot spot is going to be (and you might have, in which case we should become best friends), it will remain, at best, a guess - albeit one "backed" by more math than I would understand.