Assuming that 42 days (6 weeks) are available for preparing the quotation, the various steps leading to submission of a tender by the builder would consist of :

Days
Event
0
Enquiries/application for and receipt of blank tender document.
Day No. 1 to 3
Initial reading through of documents, perusal of drawings and decision to compete.
Day No. 4 to 31
Working out detailed quantities in the case of lump sum tenders (bill of quantities being usually not supplied in Indian tendering practice) either 'in-house' or as a ‘framed out' job. This activity is always critical when quoting for lump sum tenders.
Day No. 4 to 20
Careful reading through of documents, despatch of inquiries and receipt of
quotations from subcontractors for electrical/water supply/plumbing items etc. and from suppliers of building materials/proprietory articles.
Day No. 6 to 10
Prepare check-list of items of information to be collected. Visit to the site of work to the agency supervising the work on behalf of the owner/employer. Assessing the nature/extent and cost of all site mobilisation work like approach roads, fencing, site  offices etc. that will be needed. Assessing extent of competition that will be encountered. Discrete enquiry about the soundness of the owner/employer and his capacity to pay ensuring regular interim payments and cash flow. 
Day No. 10 to 20
Decision on construction methods, programming of work and relating these to the time allowed in the tender for completion of the work on ground. Drawing up of network if required to be submitted along with the tender.
Day No. 21 to 25
Assessing cost of overheads of fixed as well as time related nature.
Day No. 26 to 31
Work out basic unit rates (exclusive of overheads/establishment charges/profit) for all items of work in readiness for pricing the detailed quantities. It is a good policy to work out basic unit rates independently for each job.
Day No. 32 to 38
Pricing the worked out quantities at the basic unit rates and striking a total. This total when compared with the total cost of overheads for the job in question yields the percentage mark-up of the basic unit rates to cater for overheads.

Day No. 39 to 40
Establishment charges (or head office charges) expressed as a percentage for a particular builder usually remain constant for all jobs. A policy decision about the percentage of profit is made for each job depending on the size/type/nature of job. risk factors involved and the extent of urgency to secure work. Rate to be quoted for each item of work in the bill of quantities will be:

Basic unit rate + overheads, establishment charges and profit together expressed as a percentage.
Day No. 41
The bank tender documents are neatly filled up, signed and stamped. Accompanying documents like forwarding letter, instruments of earnest money, programme of work cash flow requirements/stage payment schedules etc. typed and kept ready.
Day No. 42
Submission of tender.