When you do become licensed I think that working with other investors as an investor’s agent or joining a team that specializes in investment properties is the best direction to go.

There are 20+ CPAs and accountants on this site that specialize in real estate taxation.

I agree that vacancy is harder to estimate, and talking to local PM or two like @Nathan G. suggested can give you a solid bird's eye view of the market.  

There are a few that really hustle and are successful in their first year but that takes a special person, the right brokerage, and some serious hustle.If you're going to do it, I would start by saving up six months worth of living expenses.

Do you specialize in single family or multi? 

I would highly encourage you to find a property management company that specializes in investment real estate and not just property management services.

@Aaron PetersIt's more that you find a CPA that specializes in real estate taxation to ensure that your tax return is prepared accurately and that you get every deduction you're entitled to.

I usually add on special terms, that inspection period does not begin until access has been granted to the property, financials and leases have been given to the buyer, this helps with the urgency since inspection is contingent on these things, so if they take 5 days to give them to you, your inspection starts then, and your not at any risk of losing EMD.

I own and operate a construction company that specializes in lake home properties in southern Maine.

But we need a special warranty deed signed by the initial owner, since it was never warrantied to the occupant currently there though he's been in there 4 years.Is there anyway other way to get it done it the occupant doesn't want us to send a mobile notary to the previous owners ?