Eine LOPSRM-Ausschreibung kalkulieren und die precios unitarios integrieren

Register the opportunity with the four things that decide whether it is worth pricing: the contract type the LOPSRM allows and the convocatoria chose, precios unitarios, precio alzado or mixto; the anticipo offered; whether the contract provides for ajuste de costos; and the full list of documents the propuesta tecnica and the propuesta economica have to carry. Put the junta de aclaraciones and the closing in the calendar the day you register it.

Warum: The contract type changes the whole shape of the work: on precios unitarios the quantities move and the rates do not, on precio alzado nothing moves and the risk of the quantity is yours. Firms that price first and read the bases afterwards discover this on a job they have already won, which is the most expensive order to discover it in.

Bring the catalogo de conceptos in with its claves, units and quantities untouched, and read each concepto against the especificacion that describes it. Where the description and the specification disagree, or a unit cannot carry the work described, that is a question for the junta de aclaraciones and not a decision for the estimator.

Warum: The catalogo is the contract's spine for years: estimaciones, extraordinarios and the finiquito all read against it. A clave changed at tender to make the spreadsheet tidier is a mismatch that shows up in every future estimacion, and a question not asked at the junta becomes a risk you priced without knowing you had.

Set one rate per labour category and build it from the salario base plus the factor de salario real: the days actually worked in a year against the days paid, and the statutory employer charges on top, IMSS contributions and the housing fund contributions among them. Keep the factor and the year it was computed for beside the rate.

Warum: The gap between a daily wage and a salario real is not a rounding difference, it is the whole margin on a labour heavy concepto. It also has to be defensible: the convocante can ask how the factor was arrived at, and a rate carried forward from a job three years ago answers that question with a number nobody can reconstruct.

Hold the materiales at the cost of getting them onto the site, not at the yard price, and build each machine as a costo horario: ownership, depreciation, the money tied up in it, maintenance, fuel and the operator. Herramienta menor rides as its own charge on the labour rather than as a guess inside every concepto.

Warum: The costo horario is the piece the convocante takes apart hardest, because it is where a proposal can be made to look cheap without changing anything visible. Built once from real ownership and running costs, it also survives the machine moving to the next job, which a rate invented for one tender never does.

Build each concepto as an analisis: the quantity of each material per unit of work, the crew and the hours it takes, the machines and their hours. That sum is the costo directo, and it is the only part of the price that is composed rather than applied as a percentage.

Warum: The mexico.apu_completeness rule in the validation engine exists because an incomplete analisis is the most common defect in a Mexican proposal and the easiest one to miss in your own work: a concepto with materials and no labour reads perfectly well until somebody asks who places it. Composed properly, the same analisis prices the extraordinarios later without being rebuilt.

In the bill's Markups & Overheads panel, apply the four charges in the order the reglamento of the LOPSRM fixes and on the base each one is applied to: indirectos on the costo directo, covering oficinas centrales and oficinas de campo; financiamiento on the costo directo plus indirectos, from the gap between spending the money and being paid it; utilidad on the accumulated cost; cargos adicionales on the lot, which on a federal contract is where the cinco al millar inspection fee sits. Keep IVA off the unit price entirely.

Warum: The order is not a convention, it is what the integration means, and applying utilidad to the costo directo alone or folding the cinco al millar into indirectos produces a different total from the one the convocante will compute. Each percentage also has to be supported: the financiamiento comes from a cash flow against the programme, so it moves when the anticipo or the payment period moves, and a figure typed straight in cannot answer why.

Validate the priced catalogo against the mexico rule set: the APU completeness check on every concepto, the IVA rate check that will only accept sixteen, eight or zero, the retencion flag on subcontracted lines, and the CFDI issuer data the invoicing will need the moment the job is won. Fix the findings rather than filing them.

Warum: A public proposal is discarded for a missing piece far more readily than it is discounted for a high price, and the pieces that go missing are the boring ones, an analisis with no labour line or an issuer field nobody filled in. Ten minutes against a rule set beats finding out at the apertura de proposiciones, where there is nothing to be done.

Put the two proposals together against the document list from the first step: the propuesta tecnica with the programmes of work, personnel and machinery, and the propuesta economica with the catalogo, the analisis, the basic costs and the explosion of insumos. Submission itself happens on the federal contracting platform the LOPSRM names, outside this product, so keep the exact package you uploaded here beside the tender record.

Warum: What you submitted becomes the contract, and the version on somebody's laptop is not evidence of it. A year later, when an estimacion is queried or an extraordinario is priced, the argument is settled by the analisis that went in with the bid, and the firm that can produce it in a minute is negotiating from a different position from the one still looking for it.