Lisbon/Cascais is looking popular all of a sudden - this is the third question on a similar theme in 5 weeks!!

to save repeating what's already been said I'll just direct you to these answers:

http://www.holidaytruths.co.uk/viewtopic.php?f=1&t=131519
http://www.holidaytruths.co.uk/viewtopic.php?f=1&t=132464

Given you're also looking at a second resort on the Algarve in this case I think you'd be better off in Lisbon rather Cascais. There is a list of Lisbon accommodation at http://www.visitlisboa.com/Conteudos/Menu-Principal/Home.aspx?lang=en-GB - hold the cursor over where it says "Accomodation" and a menu rises up, click on either "Hotels" or "Small Inns" then in either case click on "Place" and select "Lisboa".

This is a handy reference with location maps but if you try putting your dates in http://www.Expedia.co.uk or http://www.lastminute.co.uk you may find some discounts worth having especially if you book more than 4/5 nights. http://www.hrs.com have some cheaper places and some discounts on bigger places (as I write they have a 4* hotel in a good district at £39 for a double room including breakfasts!). A Residencial is a Guesthouse - the difference between them and hotels can be a bit blurred, last year I stayed in one and the room was identical to those in a 4 star Vila Gale Hotel !!

As for quiet on the Algarve, all I can say is try the Tavira / Cabanas area which is described in several posts below and on the resort guide (from the top of the screen). I stay in a hotel (Vila Gale Tavira) so have no personal experience of the villas but there are plenty. I do know someone who owns one on a complex at Cabanas which sounds just what you need but it's already booked from July 28th onwards, did you mean the last full week or that one?

I would recommend that you stay in Lisbon first and then move to the Algarve, it doesn't feel right doing it the other way round.

Do NOT hire a car for the Lisbon bit - it's mayhem there. If you want to drive to the Algarve book the car for the day you move. If you don't plan on using a car much on the Algarve the trains from Lisbon are reasonably cheap and fast - once you've found where they hid the ticket office - but not all resorts are connected (Tavira and Cabanas are).

Cheers Steve, thanks for taking the time to reply - legend!