Does anyone use actual mileage tracker apps they recommend? I've been using MileIQ but it's getting expensive and doesn't always capture my trips correctly.

Great question! You're right to wonder about this - a mileage log alone isn't bulletproof, but it becomes much stronger when it's part of a consistent pattern of documentation. The IRS considers a contemporaneous mileage log (kept in real-time, not recreated later) as "adequate records" under Section 274 of the tax code. But what makes it credible isn't just the log itself - it's the supporting context. If you're audited, they'll look at whether your claimed mileage makes sense given your business activities, client locations, and income reported. Here's what strengthens a mileage log: consistency in your record-keeping style, logical trip patterns that align with your business needs, and supporting documentation like appointment calendars, client invoices showing service locations, or even credit card receipts from gas stations along your routes. The key is being genuine about your record-keeping from day one. Don't try to recreate months of logs at tax time - that's when it looks suspicious. Keep it simple: date, odometer start/end, destination, business purpose. The IRS audit rate is low, but if selected, having real contemporaneous records will serve you well.

Someone posted about this same Form 8453 stock sale issue in r/tax last week! The consensus there was also that you don't need to mail anything if under $10M in sales. One important detail though - make sure the summary info you entered matches what's on your 1099-B exactly. If your basis, proceeds, or gain/loss amounts don't match what your broker reported to the IRS, you could get a CP2000 notice later asking about the discrepancy. I made that mistake last year when I rounded some numbers and got a lovely letter from the IRS 8 months later questioning the difference (even though it was like $12 total difference in tax owed).

Does anyone know if this same $10M rule applies to crypto transactions? My tax software (not TurboTax) is giving me a similar message about mailing in statements for my crypto trading, but I only had about $25k in total crypto sales last year.

Everyone's talking about adjusting allowances, but FYI the W4 form completely changed in 2020. It doesn't use allowances anymore. Now you fill out different steps about multiple jobs, dependents, and other adjustments. You'll need to fill out the new form which asks for dollar amounts in some sections rather than the old allowance numbers. The IRS calculator should give you instructions based on the new form format.

I was in almost the exact same situation last year - new job after unemployment and accidentally claimed 0 allowances on my W4. The stress is real when you see those huge tax withholdings! Here's what I learned: You're absolutely allowed to adjust your withholding to reflect your actual tax situation. The key point everyone's making about being unemployed for half the year is spot-on - your total annual income will be much lower than what payroll assumes when they see your current salary. I ended up using the IRS withholding calculator just like you did, and it suggested a similar adjustment. Changed my W4 from 0 to 4 allowances (this was before the new form) and it worked out perfectly. Got a small refund instead of the massive one I was heading toward. Don't stress about the legal aspect - adjusting your W4 for legitimate reasons like unemployment periods is exactly what the system is designed for. The IRS wants you to pay the right amount throughout the year, not massively overpay. Just make sure to use their official calculator and you'll be fine.

This is exactly why I still do paper returns. Everyone thinks I'm crazy but computers fail, software glitches, systems crash, and suddenly hours of work vanish. With paper, what you write stays written.

I feel your pain - losing hours of tax work is absolutely maddening! I had a similar experience with different software a few years back and it taught me to be paranoid about backups. Beyond what others have suggested about contacting TaxAct support, I'd recommend checking if your browser has any cached data that might help. Sometimes going to your browser history and finding the TaxAct pages you were on can reveal temporary files or cached forms that might have some of your data. Also, if you used any browser autofill features while entering information, check your browser's saved form data - you might be able to recover some of the basic info like names, addresses, and employer information that way. For next time (with any software), I learned to take a screenshot after completing each major section AND save a PDF of the return in progress every 30 minutes or so. It's a bit tedious but saves so much heartache when things go wrong. The tax software companies really need to do better with their autosave and recovery features - this shouldn't be something taxpayers have to worry about!

Has anyone used TurboTax for filing with both 1042-S and W-2? Wondering if it handles this situation correctly or if I need to go to a professional?

Just want to add some clarity on the estimated tax payment timing since there's been some confusion in the thread. You absolutely should make that Q4 estimated payment by January 15th, 2026 - this is separate from your actual tax return filing. However, there's a potential strategy you might consider: if your W-2 withholdings from January-April were substantial enough to cover 90% of your total 2025 tax liability (including the fellowship income), you might not owe penalties at all. You can calculate this roughly by estimating your total tax for the year and seeing if your W-2 withholdings hit that 90% threshold. Also, since you mentioned you're a foreign resident considered a US tax resident - make sure you understand which test made you a tax resident (substantial presence test vs green card test). This affects how certain treaty benefits apply and whether you need to file Form 8840 or other forms. Given the complexity with multi-state filing (FL and CA), treaty considerations, and mixed income types, I'd honestly recommend getting professional help for this first year. Once you understand the process, future years will be much easier to handle yourself.