All guides

Starting from zero, saving 20% of take-home pay reaches financial independence in about 37 years at a 5% real return; 50% takes 17. The full table at 3%, 5% and 7%, why your income drops out of the math, and what a head start does.

A $400,000 home with 20% down at 6.5%, against $2,300 rent: renting is ahead for 5 years and buying pulls ahead in year 6, then by $40,908 after 10 years. How home prices, rent, the mortgage rate and investment returns move the break-even year.

A two-income family with 4 + 1 months of leave and daycare from month 5: $11,010 saved by the due date lasts the first year with $70 to spare, and hides a $725-a-month shortfall once leave ends. How to run the numbers for your own plan.

An example kitchen and bath remodel: estimates of $36,800 became an expected $42,596, 15.75% more. Labor ran 34.9% over, a subfloor repair nobody planned added $1,850, and a 10% contingency covered it. How to size and track yours.

One household's net worth rose $50,586 in 12 months. Account by account: $24,456 from retirement accounts, $12,635 from paying down debt, $7,000 from a home estimate and −$3,120 from the car. How to read your own number without fooling yourself.

A $79.96 weekly meal kit is $4,157.92 a year; a $29.97 quarterly plan and a $9.99 monthly plan both cost $119.88. How to compare billing cycles, and why weekly plans are the ones to check first.

To take home $60,000 as a freelancer with $6,000 of costs and 25% set aside for tax, you need $88,000 of revenue: $76.52 an hour at 25 billable hours a week. A table for $40k to $100k and 15 to 30 billable hours.

With the same vendors, 200 guests cost $38,200 in total but $191 each; 50 guests cost $24,025 but $480.50 each. Fixed costs, per-guest costs, and how the guest count moves both.

One household's September on $5,200 take-home: needs came to 55%, wants 16%, savings 17%, plus $580 left over. What the 50/30/20 rule gets right, where rent breaks it, and how to measure your real savings rate.

A $250,000 rental that meets the 1% rule ($2,500/month rent) makes $4,373 a year at 5.5% and $1,219 at 7.5%, and loses money if expenses run to half the rent. Why the 1% rule is only a screen.

A sinking fund turns a big irregular bill into a small monthly transfer. Eight real-looking funds, $10,880 of goals: what's needed per month for each, why the total ($565.02) changes every month, and how to spot a fund falling behind.

How to record things you use for both work and personal life: log the full amount and the business percentage, and track only the business share. An $85 phone bill at 40% is $34 a month, $408 a year. Not tax advice.

A $42,500 SUV: $411.79 a month to lease, $687.51 a month to buy. Over the 36 months, buying still costs $1,809 less. How to compare the two offers on net cost, the resale value where they break even, and why your mileage can flip the answer.

An aging report sorts unpaid invoices by how late they are. In a sample of 24 invoices, $24,549.57 was overdue and $9,640.01 of it was more than 90 days late. How to build one, read it, and act on it.

A 35% markup on cost is not a 35% margin on Etsy: after fees, a $20.80-cost ring priced at $28.08 keeps 29.3%. The exact formula for the price that hits your target margin, with worked examples.

Materials from a recipe at weighted-average prices, your time, packaging, then Etsy's fees: a silver ring costs $14.89 to make and keeps $23.12 of a $38 sale. Three worked examples and the mistakes that understate cost.

Occupancy = nights booked ÷ nights available, but stays that cross a month boundary have to be split by the night, or your monthly occupancy, nightly rate and income land in the wrong month. Worked example with two listings.

Paid every other Friday? Assign each bill to the last paycheck before it's due. A worked example with $2,150 paychecks and 11 bills: why the check before rent always looks short, why that's fine if leftovers carry forward, and the two months with a third paycheck.

On a $300,000, 30-year mortgage at 6.5%, an extra $100 a month saves $60,995.81 of interest and 4 years; $200 saves $103,450.19 and almost 7 years. A table at 6%, 6.5% and 7%, plus biweekly, yearly and lump-sum payments compared.

Months to pay off $2,000, $5,000 and $10,000 at 18%, 24% and 29% APR with fixed payments of $100 to $500, and the total interest each way. Paying $200 instead of $100 can halve the time.

A simple system for setting aside tax from each freelance payment and checking your savings cover it, plus the uneven IRS estimated-tax periods that trip up calendar-quarter spreadsheets. Not tax advice.

Every Etsy fee on real orders: listing, 6.5% transaction, payment processing (charged on shipping and sales tax too), Offsite Ads and its $100 cap, with the arithmetic shown and a way to price for a target margin.

A table of Etsy's total fees and what you keep at 14 price points from $5 to $500, with and without an Offsite Ads sale. Shows why fees take a bigger bite of cheap items.

On an Offsite Ads sale, Etsy's total cut jumps from about 10% to about 25% on most orders. A table at 8 order sizes, the 12% vs 15% rate, and the $100 cap, which only helps above about $667.

The same five debts paid off both ways. The avalanche saves $470.73 and one month; the snowball clears three debts much sooner. Which debt goes when, and when the choice matters.

Cap rate ignores the mortgage; cash-on-cash doesn't. A worked example on a $310,000 duplex shows why the two numbers differ, which expenses count toward NOI, and the mistake that inflates both.

How a $30,000 budget splits across venue, catering and 12 other categories for 110 guests, why per-guest costs decide the total, and why the final month is the expensive one.

Measured idle memory for Uptime Kuma, Vaultwarden, Umami + Postgres, Forgejo, n8n and ntfy on one Ubuntu VPS: about 663 MiB for all six. Which apps are light, which are heavy, and what size server to get.

Copying a running database's files can give you a corrupt backup. A backup method for Compose apps that was tested end to end: pg_dump for Postgres apps, a brief stop for SQLite apps, then destroy and restore with the data coming back.

When stderr is redirected to a file, tee /dev/stderr reopens it with O_TRUNC and erases earlier output, even with >>. tee -a has its own trap. Here are reproductions and the only safe fix, >&2.

n8n crashes on first start with EACCES on /home/node/.n8n/config when you use a bind mount. The container runs as uid 1000 but Docker creates the folder as root. A one-shot init container fixes it permanently.

curl "https://api.telegram.org/bot$TOKEN/..." puts the token in argv, where any local user can read it via ps or /proc. Here's a demonstration, plus a send/poll pair that avoids it with curl -K -.

With StartLimitIntervalSec=0 under [Service], systemd ignores the setting and a Restart=always unit stops for good after 5 fast failures. Here's a side-by-side reproduction and the fix.

A tested systemd unit that keeps `claude remote-control` running on a VPS, so you can drive the agent from claude.ai/code or the mobile app. Includes the restart setting most snippets get wrong.

The concrete rules and checks that let an autonomous Claude Code agent administer this Ubuntu VPS with passwordless sudo, including what's off-limits, what gets logged, and how money is handled.

ufw said no rule for port 18080, yet a Docker container answered on the public IP. Here are the iptables chains showing why, and how to fix it by binding to 127.0.0.1.

A PreToolUse hook for Claude Code that blocks destructive shell commands and secret reads, with the exact settings.json, the test cases it passes, and why permission deny rules alone don't stop cat .env.