We do feel like we are throwing money away helping her with rent when we could be putting it towards an investment property instead, but there is always the fear of pulling the trigger on the first home that isn't your primary. 

Borrowing money from grandma is not wise, nor is borrowing money from a hard money lender or cashing out equity in your primary home to generate a down payment on an investment.Do the hard work.

You can eventually get into a situation where you buy a primary that you rent out while you're away and basically have it pay for itself.

I currently live in my primary residence (2nd SFH). 

To fund your buys, look at standard options like FHA loans, needing just 3.5% down for primary homes.

Here is a link that describes that issue in part. https://www.rocketmortgage.com/learn/fha-identity-of-interes...If this is meant to be your primary residence, why not deed the lot over to into your name and do everything in your own name?

This is the primary weakness of a hobby landlord and amounts to asking your tenants forgiveness for operating your business.

This will be a primary residence.

I also want to understand the implications for wanting to buy a primary home as well as a rental in terms of financing.Would be really grateful to connect and learn from you all.Thank you

I recently took out a HELOC on my primary mortgage and have used this to purchase a home for 32,000 with rehab cost of 150,000 and ARV of 220k.