Experienced flippers are more likely to understand the market, manage projects efficiently, and have a proven track record of profitability.

Asking these questions directly to the specific parties involved would be a more efficient use of time.

They are generally completed in 3-4 months and offer a much more cost efficient way to buy a nice home. 

Become more efficient/effective.

Despite lower efficiency, it seems I will be going with the central AC.

They are fast and a efficient use of your capital.

Additionally, you may also encounter unforeseen challenges during the removal of the old home and installation of the new one, which could add to the overall cost and timeline of the project.On the other hand, renovating the existing mobile home to HUD standards with the help of a contractor may be a more cost-effective and time-efficient option.

Choosing the most expensive insulation because it's the most energy efficient, should allow you to reduce and/or eliminate costs in other areas.4 - Energy efficiency isn't made up of added costs.5 - Energy efficiency is the product of reducing energy needs, not supplying added energy.6 - Cost effectiveness is a product of maximum use of materials, as in little or no waste.All of the above should be obvious, in parts. 

I am looking to put a new fence around a backyard but should I go with cedar for the long lasting durability or treated pine since it is more cost efficient?  

From a tax efficiency aspect, a lien on investment real estate equity is by far superior to 401(k) or an IRA.Paul