He bought this property as a fix and flip, and mentioned that there may be a 6 month seasoning period before a buyer can purchase the property with traditional financing. 

I'm more of a buy/fix/hold investor these days. 

Well Fargo bank now will lend up to 1 millions dollar with 20% down and fix term up to 30 years.

Most investors that fix and flip properties make $25,000 or more on a deal. 

We would like to buy another home to live in and fix up without it being contingent on the sale of our current home (even though we still plan to sell it).

Your obligation is to tell them their is no fix and that if they like they can pay to replace it with a new one.You could also buy a inexpensive one on sale and install it next spring if you are really generous.

How long will it take to fix / get online.

The good news is, this is very easy to fix.

you could add a full height pantry cabinet or a wing wall to the right side of the stove. 

I can typically get those smaller items fixed for the price of the service call or even lower and its not worth the hassle.If you are hoping to get the HVAC replaced or other appliances by them, it might work out unless it takes few more years and by then, you already spend that money on the home warranty and service call fees and they might not even cover the whole thing once it comes to replacing.They are here to make money and they will go out of their way to replace parts before replacing the entire item.