How I run a 6-figure software business, 100% solo:

𝐂𝐥𝐞𝐚𝐫 𝐬𝐮𝐩𝐩𝐨𝐫𝐭 𝐛𝐨𝐮𝐧𝐝𝐚𝐫𝐢𝐞𝐬. Only sign up for what you're willing to do. For me, that's a maximum SLA of 2-business day support, even though I'm often faster.
𝐀𝐧 𝐮𝐧𝐜𝐨𝐦𝐩𝐥𝐢𝐜𝐚𝐭𝐞𝐝 𝐭𝐞𝐜𝐡𝐧𝐢𝐜𝐚𝐥 𝐚𝐫𝐜𝐡𝐢𝐭𝐞𝐜𝐭𝐮𝐫𝐞. You can build your product however you want, but all things being equal, pick the least finicky technology and packaging.
𝐂𝐫𝐲𝐬𝐭𝐚𝐥 𝐜𝐥𝐞𝐚𝐫 𝐝𝐨𝐜𝐮𝐦𝐞𝐧𝐭𝐚𝐭𝐢𝐨𝐧. The better your docs, the more work they do while you sleep.
𝐀 𝐬𝐢𝐦𝐩𝐥𝐞 𝐛𝐮𝐬𝐢𝐧𝐞𝐬𝐬 𝐦𝐨𝐝𝐞𝐥. Deals die because of friction; rip out as much of it as you can from how you do business.
𝐀 𝐝𝐞𝐭𝐚𝐢𝐥𝐞𝐝 𝐩𝐥𝐚𝐲𝐛𝐨𝐨𝐤 𝐟𝐨𝐫 𝐬𝐚𝐥𝐞𝐬. The more you need to think, the harder it is to run the business. Automate pipeline tracking. Automate outreach. Automate your pitch.
𝐃𝐞𝐝𝐢𝐜𝐚𝐭𝐞𝐝 𝐦𝐚𝐫𝐤𝐞𝐭𝐢𝐧𝐠 𝐝𝐚𝐲𝐬. Most startups fail because they don't carve out time to grow their distribution channels. I set aside 20% of my week just for this.
𝐑𝐞𝐚𝐥𝐢𝐬𝐭𝐢𝐜 𝐠𝐨𝐚𝐥𝐬. Startups are a mental marathon. Push yourself, but stay within your means.