So, that over what i expect. and the GC extend the time frame very very long.

In extended cold snaps, I had one-month gas bill over $300.  

Even if they weren't, ANYTHING you can do to extend the life of the system is worth it, seeing as how a replacement will cost anywhere from $25K to $50K.

I also think that the business will compensate above and beyond whatever the legal terms extend.

The expense is worth it.https://www.homedepot.com/b/Search/N-5yc1vZbmgj/Ntk-Extended/Ntt-carbon+monoxide+alarm?

This may extend your closing date, but save you many headaches in the future, especially if your in a tenant friendly state.

That is because the rent-controlled apartment dwellers tend to stay in their cocoons for extended periods of time, thereby increasing demand for any available units.  

This will usually result in a extended vacancy.

I know sometime rehabs dont use materials that are suited for tenants.So keep that in mind as with tenants it may come with needs to fix things up when u want to sell again.You said that u had over extended with remodeling cost seems to me like you may have price the house too high?

So make sure you are not financially over extended.