HRV's ERV's, who knows about them?

[My Dream]

Just had an eco energy audit done and it was determined that the air leakage rate @ 50 PA; 3.97 ACH. Now I consider that really high, so we replaced all our windows, air sealed about 16 holes in the attic along with about another 10 more through out the house to bring this level to a more reasonable rate. Before I call the auditor back to do the second door seal leakage rate, I'm on the fence re the purchase of a HRV - ERV since there is a $750.00 government rebate which is offered.
I would like to improve the air quality in our home and maybe reduce the energy cost with the help of this unit. Am I on the right track and how hard are they for a DIY'er to do? I won't have problems doing the install of the unit or the electrical it's the duct work I'm wondering about.

Anyone have one?

[sailor]

I would wait with HRV/ERV for when you have ACH figures tested again. If you have enough ventilation through the envelope of the house (I don't know who in Canada sets the standards, in US ASHRAE sets up recommendations), the HRV might just cost you money (both initial outlay and ongoing electricity/maintenance costs) with only marginal increase of air quality.
Now if your house is really, really tight now (IIRC the target ideal figure to shot for in your climate is 0.2 ACH) you NEED to have some forced air exchange, especially if you use gas/propane inside.
The installation should not pose major headaches for a DIY type, for example look here: casaGURU: Install-It-Yourself HRV

I'm assuming the ACH test is done with a blower door - how much does the test cost in your neck of wood?

[My Dream]

Thanks for the reply sailor, the initial test cost $325.00 plus gst and yes it does include a blower test. The second and final audit costs $150.00 plus gst and will give me the final ACH test that you're referring to. Once I get the final reading I would no longer be entiteled to the $750.00 rebate, therefore I would have to install the HRV/ERV before the second readings, hence all the questions.