@Roxanne McClainHi Roxanne,If you are going to be a Pet Landlord, you might want to think about having "Pet Rules" for the Pet owners in the lease (a dogs paw print on the lease won't hold up in court).Then if there's a violation of your "Pet Rules" you could simply remind the resident they have to follow the reasonable rules of conduct regarding their pet, or you could (possibly) serve an eviction notice for "pet rules violation" (if your local jurisdiction will evict for that).Also an animal that has attacked a person or another animal on the property might need to be removed immediately to avoid a potential liability issue for yourself.

Obviously you need to conduct a feasibility study to determine if demand outweighs supply. 

If you do not complete extensive research then you are just guessing what might make an impact implementing into your property and business instead of having a high likelihood of knowing and stacking odds into your favor.Hotels are a more intensive asset class that can require daily management versus other commercial asset classes so you have to make sure the reward far outweighs the downside risk.

Would anybody with experience on retrofitting an older duplex with central heat and air feel like offering some advice on how extensive that project can be?

One can only hope that stores like Wal-mart and Aldi did an extensive research.

It really depends on how extensive the remodel was.

That's 18K additional cash flow annually.Then, I got a 120K HELOC to do foreclosure investing which I did extensively in 1992 to 1994.

Conduct random inspections to ensure tenants are keeping the property in good(ish) condition.4.

Use grounded three prong surge protectors; Extension cords, plug adaptors and halogen lamps/bulbs are prohibited.Use microwaves, crockpots, toaster ovens, coffee pots, hot plates and other cooking equipment ONLY in the kitchen and not in the bedrooms or sleeping areas.Not permit the use of the laundry machines for any person that is not a Tenant.Shall not bring bicycles into the interior of the Premises (other than the basement).Tenant shall not hold, conduct or throw any large parties in the Premises.Replace batteries in smoke and carbon monoxide detectors alarms, a smoke alarm or carbon monoxide detector without a working battery will result in a fifty-dollar ($50) penalty for each infraction.Change out any broken or defective lightbulbsAllow Landlord to use Wi-Fi (if applicable) and electric to power smart home devices (if applicable) i.e. smart locks and thermostats.

Generally it would be more convenient to create the LLC in the state of the property to avoid foreign filing fees, but if you end up holding the property in a land trust (which can be beneficial both for financing, anonymity and estate planning) you don't even need to pay foreign filing fees [because it is the land trust conducting business in that state rather than the LLC.]If this is your first time investing across state lines the best bet would be to connect with and experienced attorney and CPA to discuss your options and find what fits your portfolio the best.