Just lost my coach after a year and am looking for my next guidance tool.

Leverage is a great tool as well.

When I use the STR estimate tool here on BP I get the units bringing in somewhere around $45k each per year. 

A real estate attorney can help you understand your rights and responsibilities as a buyer or seller and can assist with the negotiation and drafting of the agreement.Overall, seller financing can be a useful tool for real estate investors, but it is important to carefully consider the risks and benefits and to seek professional guidance as needed.

While tools like AirDNA can be a useful resource for understanding the local vacation rental market, it's important to remember that they are based on estimates and may not always be completely accurate.

If you do not have an appraisal on hand with market rent, I would use Zillow, rentometer, deal check, even biggerpockets has a rent tool as well - good luck! 

ARM is eventually better than IO, but IO could be a good tool if you add principal every year and "structure the payment" following 3% amortization ( I did this). 

Be sure that is not the case if you choose to go that route.A heloc is a great tool if you can have access to it in order to do the updates needed.

This was before many of the tools available today and before AirBNB.  

I've been pouring over the resources here on BP, read several of the BP books, listened to hundreds of the BP and Straight UP Chicago podcasts, poured over the SAAS tools, started comping and evaluating deals and found several Meetups to attend.