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Calculators

Free tools built by the CPA who prepares the returns. Each one lists the rules and figures it uses.

All 12 calculators

S-Corp vs. Sole Proprietor 1099 Estimated Tax Planner Solo 401(k) and SEP-IRA QBI Deduction Estimator (§199A) Entity Comparison True Runway

Most used

S-Corp vs. Sole Proprietor ›1099 Estimated Tax Planner ›Withholding Checkup ›

When a tool isn’t enoughEvery calculator links to the service or model that covers the rest of the question.Send an inquiry

Services

Tax, books, elections and reporting for owner-run businesses and investors. I do the work myself, under an engagement letter that sets scope and fee first.

Form 1040 and California Form 540 Form 1120-S and California Form 100S Estimated payments Extensions Owner compensation The §199A deduction Shareholder basis Depreciation choices Go to the Tax page

Start with a calculator

Withholding Checkup ›S-Corp vs. Sole Proprietor ›Rental Property Analyzer ›

Excel modelsThe reporting package, C-to-S conversion and QSBS workbooks are built the way I build them for clients.See the models

Models

Excel workbooks for reporting and tax analysis. Licensed per user or firm; you own your copy.

Financial Reporting Package v2.1 Consolidation Edition v1.0 C-Corp to S-Corp Conversion Analyzer v2.0 QSBS §1202 Analyzer v1.0

What’s inside

21 tabs, 28,550 formulas (FRP) ›§1374 and LIFO recapture (C→S) ›Pre- and post-2025 §1202 rules ›

Rather have me run it?I can build the reporting package or run the analysis as an engagement.Send an inquiry

Services

What I do

Four kinds of work, all aimed at better decisions about the business. Each engagement starts with a letter that sets the scope and fee before anything begins.

PracticeSole practitioner

LicenseCalifornia CPA

ClientsLA and remote

Tax preparation and planning

1040 · 1120-S · 540 · 100S · An engagement letter Individual returns, sole proprietors and single-member LLCs, and S-corporation returns (Form 1120-S), with planning while decisions can still change the result.

Accounting and monthly close

QuickBooks Online · Every month · Job costing Monthly accounting in QuickBooks Online, reconciliations, the close and financial statements, cleanups of books that have fallen behind, and job costing for contractors.

S-corporation elections and entity setup

2553 · 2 mo. 15 days · 1.5% · $800 min Whether an S election makes sense at your profit level, the election itself, reasonable compensation, and the first-year setup that follows.

Financial reporting and modeling

ASC 842 · 810 · 805 · 606 · BS · IS · CF · notes · SSARS AR-C 70 Financial statement packages, technical accounting (ASC 842, 810, 805, 606), opening balance sheets after an acquisition, cash forecasts and decision models.

I don't prepare C-corporation or partnership returns, and I don't perform audits.

When the answer needs judgment, ask me.

Send a few sentences. If it fits, you get an engagement letter with the scope and fee, and the IRC §7216 consent forms. Documents go through the secure portal.

Send an inquiry