Average time to get paid is within 30 days of bill date. General contractors have different billing cycles; some once, some twice per month. Bills are paid in draws if the subcontractor is on site for more than 1 billing cycle.
If a project is in progress and contractors billing cycle ends, cleaning company can bill contractor for percentage of completion of invoice to be applied to current billing cycle. Then wait 30 days to receive payment. (example. job will take 3 months to complete, contract amount $30,000. After month 1 you are 50% complete, you can invoice $15,000 the first month because this is 50 % of completion. Cleaning company can negotiate payment terms directly with the general contractor.
If you are asked to submit a proposal with 4 line items. example ( rough clean, final clean, vct waxing, exterior windows) you can not bill per line item. You will bill based on how much of your contract is complete at the bill date
In 700 awarded jobs, we have seen the cleaning company be paid % or full contract 7 times. Depends on the contract and how desperate they are to have you clean the building. We have never seen a company be paid weekly.