The Portuguese colonization in africa during the 1400s and 1500s usually consisted of trading expeditions, most often funded by the crown, but private expeditions were also not unheard of.

After the first few "discovery journeys" suitable places for "colonization" were decided upon. These places were generally existing centers of trade, or natural harbours that were already being used by the natives to trade with eachother or with arab traders.

For the most part the colonization consisted of sending a few expeditions to negotiate with the locals in order to build a "Feitoria".

Feitorias were somewhat of a mix of a factory, a fort and a market, and were used to primarily as a trading post as well as a resupply point for ships coming and going. They had a permanent garrison, though the size of it depended on the size of the feitoria. The first one was built in Arguin in 1448, and until the 1600s around 50 of them were built on the african coast.

Also, your point about women and children doesn't really make sense, in the context of Portuguese exploration and colonization, because unlike british or french colonial policy, the portuguese colonial policy encouraged having native wives and children as a way to not only maintain good relations with the locals, but to strengthen portuguese presence in the area. So when you ask "were there women and children living in the feitoria" the answer will almost always be yes, however those women and children will almost always be native women married to portuguese soldiers/sailors stationed there, and their children, not ethnically portuguese woman brought from Lisbon.

As for communication, it was at first done through common languages, that although not widely used in the region, were known, most importantly arabic. Later on natives who learned portuguese were occasionally brought on in order to serve as interpreters.

Hi, I will just take liberty to give an answer to this bit of your question:

When first contact was made with sub Saharan African communities how would Portuguese (or other nations) communicate initially? Was there any common languages spoken like Arabic?

I am currently reading letters from Alvise Cadamosto, Venetian in the service of the Portuguese, who sailed around West Africa in 1455-1456. What is nice, project Gutenberg hosts the letters for free, as they were published inside "A General History and Collection of Voyages and Travels — Volume 02" by Robert Kerr from the year 1824.

In the book Cadamosto clearly states several times that they use previously acquired slaves to communicate in new areas. I am now just going to copy paste the relevant excerpt from the book regarding the exploration of the part of Africa between rivers Senegal and Gambia (Chapter IV, Section VII):

Every ship which sails from Portugal for the coast of Africa is supplied with some of these negro interpreters, who consist of slaves that had been sold by the lords of Senegal to the first Portuguese who touched on the coast, and who have learnt the Portuguese language and become Christians. These are hired from their masters in Portugal, who receive, for their hire, a prime slave from the cargo on returning from the voyage; and when any of these interpreters have thus earned four slaves for their master, they become free.

Also in the previous chronicles of Portuguese discoveries down the cost of West Africa up to 1440s (so 10 years before Cadamosto) "The Chronicle of the Discovery and Conquest of Guinea. Vol. I" by Zurara (full 19th century translated text also freely available on project Gutenberg here ) it is several times mentioned that they used previously acquired slaves to do the translating. The difference being that the first slaves were captured by the Portuguese's exploration-raiding parties, but later in Cadamosto's texts, after the establishment of the fort and freitoria at Arguim, by trading with locals.

P.S. Also, an interesting making first contacts in Zurara's chronicle was a story of certain John Fernandez (that's what the english translation calls him, he would probably be João), who also probably knew Arabic. He has actually volunteered to come off ship alone and spend 7 months in the the area of Azanhaji the Berber people who lived in sahara over a large area north of the Senegal river, to learn as much as he can about the area and report back to the Portuguese.Which he did, while establishing nice relations with the locals in the process! But this is actually about Berbers in the Sahara area, so does not really fall under "Sub-Saharan Africa" part so i just leave it as a side information