Last question first: The dominant noise will be blade tip turbulence noise, so unless using an in-line blower with silencer beyond it toward the outside, a silencer will not help your neighbors.

For cooling capacity, I suggest the following. Assume actual flow is 1000 cfm. This implies that your whole house air is replaced every 8 minutes. Find the density of air and calculate pounds per hour moved. Find the specific heat of air and calculate the energy required per hour to cool the air by X degrees. Being careful to operate in consistent units, calculate the BTU/hr needed. This will establish the size of the air conditioning needed.

Note that this is only needed when on full power; alternative schemes that include thermal capacity at the cost of space may allow a more economical heat pump. (Imagine making ice cubes and then blowing air through them.) The answer for peak air flow may end up near or beyond 100k BTU/hr, which is a fair amount of air conditioning.

Anoher solution is an outdoor grill used when it is hot out.

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