When an S&P/ASX 300 Index (ASX: XKO) share is trading substantially below its underlying value, I think it's a great idea to invest while the opportunity is there.
The two businesses I want to highlight in this article both have excellent long-term potential – one because of the longevity of the assets it owns and the other one because of its growth runway.
I already own a piece of both of these ASX 300 shares and I'd happily invest more if someone gave me $5,000 to invest in them.
Image source: Getty Images
Rural Funds Group (ASX: RFF)
Farming has been an important asset for many centuries, if not thousands of years. We all need to eat food, so I imagine its assets will remain in demand for the rest of my lifetime (and beyond).
The business is a real estate investment trust (REIT) that owns farmland across Australia, which includes cattle, almonds, macadamias, vineyards and cropping farms.
Pleasingly, Rural Funds' properties are spread across different states and climate conditions, giving the business pleasing diversification.
Rural Funds has long-term leases with its tenants, giving the business pleasing income security and visibility. Some of its tenants include names like Select Harvests Ltd (ASX: SHV), Treasury Wine Estates Ltd (ASX: TWE) and Australian Agricultural Company Ltd (ASX: AAC).
The ASX 300 share has in-built rental increases with most of its contracts, which are predominantly either linked to inflation or the increases are fixed at an annual pace each year. This gives the business a pleasing tailwind for rental profit growth and an improvement in the underlying value of the farms.
It reported its adjusted net asset value (NAV) was $3.08 at 30 June 2025, so the current Rural Funds unit price is trading at a 36% discount to this. That's a very attractive discount!
Siteminder Ltd (ASX: SDR)
Siteminder is a tech business that provides software for hotel management and booking.
The business is responsible for helping hotels generate more than 130 million reservations worth more than A$85 billion in revenue each year.
This ASX 300 share is truly a global company, with offices in Bangalore, Barcelona, Berlin, Dallas, Galway, London, Manila and Mexico City.
The company wants to achieve 30% annual revenue growth in the medium-term, which it could achieve through winning new subscribers and offering them more advanced software to help subscribers maximise their revenue.
Siteminder is seeing its gross profit margin increase over time thanks to operating leverage and efficiencies.
I'm expecting the company's operating profit (EBITDA), net profit and free cash flow margins to increase in the coming years as revenue rises. If revenue can continue growing at a compound annual growth rate (CAGR) of more than 20% over the next few years, then I think the business could be substantially undervalued today.
Since 29 October 2025, the Siteminder share price has dropped by 24%, making this growing business a lot cheaper. I think this ASX 300 share could be a top performer over the next five years.
