Ask HN: What is the best way to invest my first $5k in profit?

Hi there. I’m looking for some advice regarding how best to invest some cash. I’ve recently started a web services company and have had two small, successful website projects that have left me with $5,000 profit. Great start but they are pretty much one off projects without much hope of recurring revenue.

I’ve got a day job in IT management making around $150k but would like to transition to working for myself. I’ve got a crew of folks who are willing to work with me and can fill gaps on projects in areas I’m not great in such as sys admin, business analysis, and database administration. I'm open to going wherever the money is.

Before moving into management (and now on the side) I did full stack web dev. As such, I’ve done everything from fully custom enterprise apps to CRM projects to Wordpress landing pages to e-commerce sites. But I’ve mostly worked for other companies, hence why I’m a little less sure of what to do in this situation. One last bit of background, I can tolerate a bit of risk as I’m not the only income/insurance provider in my household but need to keep my job until I can do so without catastrophic financial impact.

A few questions for you all:

Should I be optimizing my business to serve e-commerce clients? This seems to be an area where there is a lot of potential for recurring revenue tied to overall sales of your customers.

Should I use my “war chest” to start advertising my services?

What areas should I focus on providing services that have a high revenue yield?

Thanks for your advice in advance!