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Taxes, portfolio, signals and AI — in plain words, with checked numbers.
RSS- AI
AI Investing Assistant: What It Can and Can't Do for You
How an AI investing assistant differs from a general chatbot, what to ask it, how to check its answers and where its limits are. With example prompts.
· 7 min read - Taxes
Modelo 720 and 721 in Spain: Who Files and By When (2026)
Modelo 720 and 721 explained: the 50,000 € threshold, the +20,000 € re-filing rule, the 1 Jan–31 Mar deadline, penalties after the EU ruling, crypto wallets.
· 7 min read - Signals
Do Chart Patterns Work? What a Backtest Actually Shows
Do chart patterns work? How a backtest measures them, how success is defined, why a 60% hit rate can still lose money, and the biases that inflate results.
· 8 min read - Portfolio
How to Calculate Portfolio Return: TWR, XIRR and Examples
Calculate portfolio return correctly in 2026: simple return, time-weighted (TWR) and money-weighted (XIRR), deposits, dividends, fees and FX, with examples.
· 6 min read - Smart money
13F Filings and Insider Trading: Following Smart Money
How to follow smart money in 2026: what Form 13F shows and hides, how to read quarter-over-quarter changes, what insider Form 4 trades mean and the traps.
· 7 min read - Taxes
Crypto Tax in Spain 2026: Rates, FIFO and What to Declare
How crypto is taxed in Spain for residents: 19–30% savings rates, FIFO, taxable crypto-to-crypto swaps, staking, losses and what goes in Modelo 100.
· 8 min read - Taxes
Stock and Dividend Tax in Spain: 2026 Guide for Investors
How Spanish tax residents pay tax on shares, ETFs and dividends in 2026: 19–30% savings rates, FIFO, the 2-month rule, loss offsets and US withholding.
· 7 min read - Signals
Qullamaggie Swing Trading Rules: Setups, Stops and Exits
Qullamaggie swing trading rules: breakouts, episodic pivots, opening range entries, stops at the day's low, partial sales and MA trailing, plus our backtest.
· 7 min read - Portfolio
How to Track a Stock and Crypto Portfolio in One Place
Track your stock and crypto portfolio across exchanges, brokers and wallets: read-only API keys, CSV imports, EUR conversion, FIFO and a security checklist.
· 7 min read
SaVa.Team