In a market where share prices are often highly in flux regardless of what the underlying businesses behind them are doing, it's more important than ever to not only be highly selective about the companies you buy but make sure your investment thesis is fully formed before you press the buy button. When you're investing in companies that you intend to hold onto for several years at least, this time horizon can also help you separate the wheat from the chaff in identifying the businesses that make the most sense for your portfolio. 

Today, we're going to look at two companies that are continuing to make progress in an unpredictable operating environment and disrupting their respective industries in the process. If you're looking for stocks to add cash to this month, you may want to consider adding one or both of these to your buy list. Here's why. 

1. Airbnb 

Airbnb (ABNB -1.52%) is trading up around 62% since the start of 2023. The company already controls about 20% of the vacation rental market, but its platform revolves around so much more than leisure travel. With a selection of stays that span over 200 countries and counting and cater toward vacationers, business travelers, digital nomads, and everyone in between, it's not hard to see why the platform remains incredibly sticky for consumers as the travel industry is getting back to or even surpassing the pre-pandemic normal.  

Whether you want to have an entire apartment to yourself, enjoy a boutique luxury stay, live with a local in a foreign country, or find whatever type of booking suits your needs, Airbnb allows you as the traveler to do so with ease. A record number of hosts are listing their homes on the platform to capitalize on the demand for Airbnbs around the world. Airbnb reported that active listings jumped 18% year over year in the first quarter of 2023.  

For current or prospective shareholders, beyond the market leadership and stellar financials Airbnb continues to demonstrate, there are a few notable reasons to like this business and where it's headed. For one, Airbnb caters to both sides of the relationship when it comes to booking travel accommodations. Its platform draws hosts from around the world looking to make an income while also catering to any type of traveler looking to go to almost any travel destination. 

Second -- and perhaps even more importantly -- Airbnb facilitates this two-sided relationship with essentially no overhead costs. The company doesn't own or operate most of the properties listed on the platform and makes most of its revenue and profits from booking fees (i.e., service fees). 

Like any company that operates in the travel space, some investors might be worried about what another shift in consumer spending might mean for Airbnb. It's worth pointing out that even as concerns about a recession haven't abated by any means, consumers still appear to be flocking in droves to spend money on travel. And because it's not just leisure-seekers booking on Airbnb, the versatility of its stays also lends a certain measure of resiliency to this business. Looking over the long term -- three to five years at a minimum -- this still looks like a solid business well worth buying and holding onto. 

2. Upstart 

Upstart (UPST 3.34%) has seen shares jump 245% since the beginning of this year. The company is steadily expanding its footprint in the lending market with a uniquely disruptive value proposition for both consumers and lenders. On the consumer side, Upstart's platform provides a seamless and straightforward way to apply for various types of personal loans as well as auto loans. The company's platform processes loan applications on a 24/7 basis, and 70% of consumers access its services on their mobile devices.  

Not only are 84% of all loan approvals now fully automated, but 90% of small-dollar loans don't involve any human intervention. Because Upstart's model leverages a far wider range of factors beyond the FICO-score-only model (i.e., income, education, and work experience, to name a few), consumers who had historically been left out of the lending markets simply because of their lack of credit history are now gaining access to lending products.  

On the lender side, Upstart's platform not only opens up new sources of revenue, but because its artificial intelligence and machine-learning-backed model is constantly attuning to the environment at hand, its lending partners like banks and credit unions can have greater confidence in the loans they're paired with. Upstart is unprofitable again, and revenue has decelerated, but this is largely because loan volume is still down from prior periods, and it's had to fund more loans with its own balance sheet. 

The company announced multiple outside funding agreements that should help slash the quantity of loans it's carrying, which are still in the minority of the loans it processes overall. As for the decline in loan volume, that can be attributed to a few factors. Fewer consumers are applying for loans, given the high interest rates right now. Institutional investors are also more cautious with funding loans, given the elevated cost and risk of doing so. Also, the fact that Upstart's model calibrates to the macro and risk landscape (which means that currently it approves fewer loans on the whole, and approved loans carry higher interest rates) is playing a role. These are issues that should ease with time.  

On the positive side, Upstart is in the process of getting ready to dive into home equity loans later this year. Management noted in the company's first-quarter earnings call that 95% of home equity line of credit products (HELOCs) are funded by banks and credit unions, so this is tried-and-tested ground for its growing network of lending partners. This also represents a nearly $3 trillion addressable market for Upstart and a space that, due to its high level of fragmentation, offers considerable room for expansion. There's plenty of room for this business to grow as economic conditions and lending volume recovers, a reality that may induce some investors to take a second look at the fintech stock.