@Troy S. correct me if I'm wrong, but we have three interior compact duct units, two exterior condensers, and 3 wall evaporators.

We put down foamboard insulation before the slab was poured for comfort and to give us the flexibility to put down finished flooring afterwards without fear of condensation issues.  

Case in point is $5K for an AC condenser.  

This proved to be a good thing as I started freeing up more time for my primary businesses at the time, an online high end furniture store and real estate.I realized that I condensed 5 years worth of failures into 5 crazy months.

The pipe HAS to be insulated well so water doesnt condense and drip downAs stated Broan is good since you can get repairs for years down the line (as already mentioned above)

I don't do it because I have seen it condense and trap moisture on the inside.

.-1-ARUG42C14A Air Handler-1-GSX13042 Condensing Unit (3.5 ton - 13 seer)-Disconnect and remove existing air handler in closet-Install new platform and seal return air chase-Reinstall existing air handler-Repair wiring and reconnect ductwork-Install new refrigerant lines-Remove existing condensing unit-Install new condenser listed above-Reconnect electrical to equipment-Restart system and check operationTotal - $5,450Please let me know if you guys think this is reasonable or if anyone has had experience with this.

Tenants know I do a series of other maintenance items on the same trip.This is my basic list.(1) Replace AC filter.(2) Bleach AC condensate drain line.(3) Test thermostat and replace batteries if necessary.(4) Exercise ALL shutoff valves - kitchens and bathrooms.(5) Inspect and feel around under sink drains for moisture and leaks.(6) Open toilet tank and look at the tank bolts and overflow tube.(7) Test garbage disposer and throw some ice down.(8) Test smoke and fire alarms. 

Roof - $8k (no carpentry)Siding - $9kElectrical - $10kNew AC Condenser - $3k

It's tough to take a 6 month house flip, capture content the entire time, and condense it all into a 15 minute YouTube video (I know from experience)Bigger Pockets is by far the best resource on the internet for real estate investing education.