Buying a new primary residence has nothing to do with the capital gains exclusion.It is when you go to sell the new house down the line you'll run into a problem.

This is like buying any other property, it is valued at whatever the market is.  

2. how to know where to find a B,C,D areas\neighborhoods in cities\ countries.3. how do I know if a property is worth the checking\ buying?

Investment Info:Single-family residence buy & hold investment.

You need to be careful about where you're buying and what your expectations are.

If it's posted in Florida MLS, it's available in all online sites and people who are looking to buy property in your area can find your listings. 

If you don't want to put a single dollar down then you can just structure a 100% financing with the sellerHey Ko, it’s nice see you again.I’ve spoken with the seller and they want a 10% down.I think I’m going to wholesale this deal if I can get good terms, but every once in a while I come across a good deal that I would like to purchase as a buy and hold.what type of loans would you recommend for traditional buy and hold? 

I have been wanting to buy this piece of land for years and it has recently become available.

For a number of years I've formed transactional partnerships (form an LLC with single or multiple members to buy a building, build condos, townhomes etc).

Consequently,  there's rarely enough of a deviation in price between these auctions and what you can buy on the MLS/elsewhere with full diligence capabilities to make these transactions worthwhile.