Typically, removing smells from drywall/sheetrock requires either complete removal and replacement or the use of stain blocker primer paints or other chemicals.

I need to compare the profitability as well as tax ramifications for two options I’m grappling with. we currently own a home in which the tenant is in a lease w/ an option to purchase -but the contract is coming to an end soon and she does not have the ability to purchase the home/get a conventional loan yet- but desires to work toward that.

I know the 1% rule isn't everything, but it is an easily comparable metric. 

We don’t know any PMCs to recommend in the area mentioned, but since selecting the wrong PMC is usually more harmful than selecting a bad tenant, you might want to read our series about “How to Screen a PMC Better than a Tenant”:https://www.biggerpockets.com/member-blogs/3094/91877-how-to-screen-a-pmc-better-than-a-tenant-part-1-services-and-processesWe recommend you get management contracts from several PMCs and compare the services they cover and, more importantly, what they each DO NOT cover.

Don't compare interest rates, compare velocity.You want to have access to emergency cash for issues with the rental, so you'll always be setting aside a portion of the rent to that purpose rather than paying it back to the mortgage.

There are also wallpaper removal chemicals from Home Depot.

If it works out, it'll be 3 large fourplexes on 1.5 acres in Apache Junction, AZ, with a total of about 20k sf.I'd be happy to connect and compare notes with anyone else who has done something similar.

@Joe SplitrockIf it was a rental first then you owe taxes based on the percent of time it a rental compared to total owned time. 

Would love to compare notes with anyone. 

Educate yourself on what a good property manager looks like, then shop around and compare prices.