Faro's island is one of the most remarkable cases of clandestine building, offering "discreet" cheap renting.
You must have a friend that knows a friend of someone that has a friend... We had, and that allowed us to stay cheaply in one of the legal houses (I think) of the island.
The construction is chaotic but, with such a narrow stripe of sand, everybody is close to the water. Many irregular houses were destroyed, but the remains are not exactly a good example of city planning.
In the positive side, it's a quiet and safe area for families.
Google Earth is perfect to give you an idea of what I mean!
Don't forget that the city of Faro itself doesn't have a beach. There are however boats that take you to some islands nearby and there is a beach accessible by car (but in summer it can get quite crowded). However this beach is at least 5 kms away from the centre.
We arrived in Faro off the train and immediately started downtown to find our accommodation (with a totally hopeless map!!) We were speaking to each other in English, and wearing backpacks, when a fellow casually dressed approached us and in a posh British accent asked if we spoke English. We were on the alert immediately but also did not want to be rude.
He told us he had lost his money (thieved) and was only a couple of dollars short of the bus fare home, could we help him out. This was really hard to do...but we said no. We said we only had our credit cards. We kept walking.
I felt really really bad until we got to our accommodation (no help from the map) and told the hostelier - he said we did absolutely the right thing. It's a scam.
When buying anything that is sold as leather keep your witts about you as many of the goods are fakes and good fakes at that with all the right markings and many been sprayed with a leather scent. Easiest way to tell is look at the price, if it looks to good to be true then it is.
When walking in many areas of the algarve street sellers will offer you gypsy gold, don't buy it it's not gold. Also you'll be offered drugs if your under 30, simply decline and they will politely disapear as quickly as they appeared.
1)ON THE BEACH - Remember that the sun of the Algarve tans but it can also burn. Take full advantage of your days on the beach avoid over-expoure. On the beach have fun but do it safely avoid areas that are post signed as dangerous or have no life guards. Follow the language of the Flags (RED flag bathing is forbidden, YELLOW flag swimming is forbidden, GREEN flag = the ocean is yours to swim and play in). Children need attention all time. Drink plenty of water the sun dries out your body. On boats always use a life-jacket. 2) ON PUBLIC PLACES - Remember that you are in a different country, with a different cultural background. Do not expect to find here what you left at home (in your country). The Law and procedures in case you break the Law might be very different from what you are used to. You are a guest... behave like one. Most of the time I spend at court is helping people that broke the law and still do not accept the fact that things are done differently. 3) DRIVING - Portugal has the worst driving accident record of all European Union. In the Algarve you must be extra carefull. There will be many drivers not used to the roads and traffic may be slow during peak season especially in and out major cities.