Do you have someone who can stay in it (or yourself) while it is vacant?

If they want to stay, verify they can afford it.

You can not partner with relatives or have them do any work on or stay in your properties. 

While traveling back and forth to Philadelphia, I stayed in a rental in downtown and met a real estate agent in passing.

Setting clear, achievable goals will help guide your decisions.When it comes to getting finances in order are you keeping a budget and know where every dollar you spend goes? 

Can anyone point me to a step-by-step guide for end buyers working with wholesalers?

To stay away from that, I've kept it to two, up front fees.

Determine how much money would be needed to handle each risk, and determine if you have sufficient liquidity / cash flow to ensure you can “stay in the game”.This is of course in addition to all normal “due diligence”, financial forecasting, etc. 

Most of my clients buying STNL or MTNL stay in certain price ranges.

You might also consider forming an LLC to manage the property-related business activities while holding the property in your name to stay within your lender’s requirements.Explore safer rental strategies: If you’re open to short-term rentals, Airbnb’s Host Guarantee provides additional liability coverage, which may offer peace of mind while keeping the property in your name.