Spent a bit of time exploring this in Hero Lab. Keeping in mind the Availability 12 limit at chargen, here's what I came up with
* Skillwires 4 (Used) - 60,000 nuyen, 0.5 essence
* Skilljack 4 - 80,000 nuyen, 0.4 essence
* Chipjack 6 - 6,000 nuyen, 0.3 essence
Total: 146,000 nuyen, 1.2 essence
This gives you the ability to run up to 20 Rating points of Skillsofts (30 points with Wireless), with a maximum rating of 4 each, and 7 physical slots for holding Skillsofts. That works out to 5 level 4 skills (or 7 level 4 and one level 2 with wireless) that you can have active at one time. You can save an extra 20k by making the Skilljack used...it only adds 0.1 to the total Essence cost.
Rating 4 Skillsofts aren't cheap - 20,000 for Activesofts, 8,000 for Knowsofts, and 4,000 for Linguasofts. However, a dedicated "skillwire guy" can buy a new Activesoft every 3-4 adventures and still have enough left over for Lifestyle and basic expenses. It's also worthwhile to have some cash on hand - with Availability of 8 / 4 / 2 for Active/Know/Linguasofts, it's pretty easy to go to your fixer or similar contact and acquire one during an adventure.
A character with Priority A Resources can have this, 5 activesofts, and over 200k nuyen for other ware and gear. It is viable to do a skillwire character on Priority B, and still have some nuyen left for some ware and a few activesofts. You can even do it with a C in Resources (if you go with a used Skilljack), but you'll only be able to have 1 starting activesoft.
For reference, there are 57 non-Magic Active skills in the core rulebook (excluding Exotic skills), broken down as follows:
Agility: 15
Body: 2
Reaction: 5
Strength: 2
Charisma: 9
Intuition: 5 (excluding Assensing)
Logic: 18
Willpower: 1 (excluding Astral Combat)
That's over a million Nuyen if you bought every Activesoft at level 4...though you'll have skills of your own and many skills are used extremely rarely (Nautical Mechanic?). It's feasible to get every skill you'll want for the character over the course of a campaign. Or, if you're having a rough run, pay 20k to subscribe to the Platinum Wireless Skillsoft Network for a month. If you have to have that Locksmith skill to get past a security door, you may be able to get your team to split the cost.
Upgrading to a higher level of Skillwires is also feasible, though you can't upgrade Skillsofts and would have to buy new ones at the higher level to take full advantage of the upgraded ware.
If you don't want the stigma of used cyberware:
* Skillwires 3 - 60,000 nuyen, 0.3 essence
* Skilljack 3 - 60,000 nuyen, 0.3 essence
* Chipjack 6 - 6,000 nuyen, 0.3 essence
Total: 126,000 nuyen, 0.9 essence
You're now under a point of Essence for the wires, and can run 6 level 3 skillsofts (or 9 with wireless on). Each Activesoft costs you 15,000, Knowsofts are 6,000, and Linguasofts are 3000.
Finally, just for fun:
* Skillwires 1 - 20,000 nuyen, 0.1 essence
* Skilljack 1 - 20,000 nuyen, 0.1 essence
* Chipjack 6 - 6,000 nuyen, 0.3 essence
Total: 46,000 nuyen, 0.5 essence
For half a point of Essence and under 50k, you get the ability to have a basic understanding of every skill. You can run 14 level 1 Skillsofts simultaneously (21 with wireless on). Buy every non-exotic Active Skill in the game at level 1 for under 300k, and have money left over to get a few exotics. Just be careful with that Monofilament Whip!
Also, for a mere 2,000/month, you can get a basic Wireless Skillsoft Subscription, which lets you download and run a single level 1 Knowsoft at a time. With high Logic and Intuition, you can get 6 or 7 dice in any Knowledge skill. Bonus points if you add a Cerebral Booster and/or Cerebellum Booster. Impress your friends with your knowledge of Underwater Basket Weaving and Cheese Dips of the Yucatan!