If your hesitation is resting on inability / delay in qualifying for your second.. 1) most importatnly, you need to start with one..and househacking with low down is the best way to start. 2) buy that first one with intent of leveraging it to buy the 2nd/3rd property, IE live-in flip or find a motivated seller offering a steep discount.

Just waiting for investors to buy at a discount or make creative offers.  

That said, expect to deal with a fair amount of fluff leads.The two best strategies I’ve found are inbound methods: direct mail and Google Ads.Direct mail can be expensive, but it can also yield highly discounted properties.Google Ads, on the other hand, doesn’t require data extraction like calls, direct mail, or texting.

I think it is time for me to have a property management software of some kind to manage my long-term rental properties going forward.

When you get larger, migrate to a property management software that automates these things.

Why don’t I purchase a house under my LLC then overtime sell it to my personal retirement IRA at a discounted rate.

I wouldn't call that a true "DSCR Loan" - especially considering that a ground-up construction property won't have any cash flow so DSCR would be negative or 0 numerator if you'd try to calculate it ground up multifamily is not 0 cashflow there are hundreds of thousands of apartments built every year, leased up, and sold for a profit as well. we build not only at a discount for investors but 1% on infill lots I'd be really careful with all your absolutes. you can get land for 10k in columbus on lots you can build 2-4 units on in one of the cheapest construction markets in the country.

In particular, is there any software/tooling which is typically used to analyze & find tenants, analyze deals, and used to find a local realtor who specializes in real estate investing?

Referals are always great, you could provide current tenants a discount for anyone they get to sign.

I learned the hard way that things can go wrong quickly, and if you don't have cash in place, you might be forced to sell at a discount.