Consultation/price estimates are generally free. So just call around - find out first if you are comfortable with an 'individual' or a company (like merry maids, etc).
Then just have them come for an estimate. They will give you a first time cleaning fee (which is generally about double the 'regular' cleaning fee).
Often times the first time cleaning fee will be lower IF you are planning to put them on a regular cleaning schedule (such as every week, every other week, some might be okay with even once a month).
But generally the first time or one time cleaning fee is going to be much higher than a 'regular' cleaning fee.
ALSO, generally company web site and those coupon packs you get in the mail will have a discount coupon that you can use too off your first cleaning.