Typically, the owner is the only one that can sign a lease as they are the owner of the property.

and are there any good online templates I can use for PA and what's the best free way to do eSignatures? 

Or can it be created right before the property is sold? 

If you’re running a MTR more like a STR, then you can decide to charge the full boat as agreed or, if you desire (possibly to obtain a good review) find a substitute renter for the period in question and credit the original renter.If, like me you operate a MTR more like a LTR just for a shorter period of time, you probably use a specific rental form provided by either the state real estate commission of the local NAR affiliate.  

Your PM can run their business however they want.

Renting by room can be tricky and is why a lot of PMs try avoiding it.

I'm just curious should I furnish the place or just keep it empty and people can move their own stuff in and just drop the minimum lease duration to 3 months?   

You’ll find a lot of experienced investors here who can help with tips, and I’m sure your own insights will add value to the community too.

Then drywalling and everything else can be done by your contractor.

@Ori Skloot can you give more details on the electrical and plumbing work you did?